LOAN AGREEMENT

                                      AMONG

                 AMERICAN TOWER SYSTEMS, INC. (THE "BORROWER");

            THE FINANCIAL INSTITUTIONS WHOSE NAMES APPEAR AS BANKS ON
             THE SIGNATURE PAGES HEREOF (COLLECTIVELY, THE "BANKS");

                                       AND

                         TORONTO DOMINION (TEXAS), INC.,
                             AS ADMINISTRATIVE AGENT
                   FOR THE BANKS (THE "ADMINISTRATIVE AGENT")


                          Dated as of November 22, 1996




                       Powell, Goldstein, Frazer & Murphy
                                Atlanta, Georgia




<PAGE>





                                 LOAN AGREEMENT
                                      AMONG
                 AMERICAN TOWER SYSTEMS, INC. (THE "BORROWER");
            THE FINANCIAL INSTITUTIONS WHOSE NAMES APPEAR AS BANKS ON
             THE SIGNATURE PAGES HEREOF (COLLECTIVELY, THE "BANKS");
                                       AND
                         TORONTO DOMINION (TEXAS), INC.,
                             AS ADMINISTRATIVE AGENT
                   FOR THE BANKS (THE "ADMINISTRATIVE AGENT")


                                      INDEX

                                                                            Page

ARTICLE 1         Definitions...............................................  1

ARTICLE 2         Loans..................................................... 20

         Section 2.1                The Loans............................... 20
         Section 2.2                Manner of Borrowing and Disbursement.... 20
         Section 2.3                Interest................................ 24
         Section 2.4                Commitment Fees......................... 25
         Section 2.5                Mandatory Commitment Reductions......... 26
         Section 2.6                Voluntary Commitment Reductions......... 28
         Section 2.7                Prepayments and Repayments.............. 29
         Section 2.8                Notes; Loan Accounts.................... 30
         Section 2.9                Manner of Payment....................... 30
         Section 2.10               Reimbursement........................... 31
         Section 2.11               Pro Rata Treatment...................... 32
         Section 2.12               Capital Adequacy........................ 32
         Section 2.13               Bank Tax Forms.......................... 33

ARTICLE 3         Conditions Precedent...................................... 34

         Section 3.1                Conditions Precedent to Initial Advance. 34
         Section 3.2                Conditions Precedent to Each Advance.... 35

ARTICLE 4         Representations and Warranties............................ 36

         Section 4.1                Representations and Warranties.......... 36
         Section 4.2                Survival of Representations and
                                    Warranties, etc......................... 44

ARTICLE 5         General Covenants......................................... 44

         Section 5.1                Preservation of Existence and Similar
                                    Matters................................. 44
         Section 5.2                Business; Compliance with Applicable
                                    Law..................................... 45



<PAGE>


                                                                            Page


         Section 5.3                Maintenance of Properties............... 45
         Section 5.4                Accounting Methods and Financial
                                    Records................................. 45
         Section 5.5                Insurance............................... 45
         Section 5.6                Payment of Taxes and Claims............. 46
         Section 5.7                Compliance with ERISA................... 46
         Section 5.8                Visits and Inspections.................. 48
         Section 5.9                Payment of Indebtedness; Loans.......... 49
         Section 5.10               Use of Proceeds......................... 49
         Section 5.11               Real Estate............................. 49
         Section 5.12               Indemnity............................... 50
         Section 5.13               Interest Rate Hedging................... 51
         Section 5.14               Covenants Regarding Formation of
                                    Restricted Subsidiaries and
                                    Acquisitions; Partnership, Subsidiaries. 51
         Section 5.15               Payment of Wages........................ 52
         Section 5.16               Further Assurances...................... 52

ARTICLE 6         Information Covenants..................................... 53

         Section 6.1                Quarterly Financial Statements and
                                    Information............................. 53
         Section 6.2                Annual Financial Statements and
                                    Information............................. 53
         Section 6.3                Performance Certificates................ 54
         Section 6.4                Copies of Other Reports................. 54
         Section 6.5                Notice of Litigation and Other Matters.. 55

ARTICLE 7         Negative Covenants........................................ 56

         Section 7.1                Indebtedness of the Borrower and its
                                    Subsidiaries............................ 57
         Section 7.2                Limitation on Liens..................... 57
         Section 7.3                Amendment and Waiver.................... 57
         Section 7.4                Liquidation, Merger or Disposition of
                                    Assets.................................. 58
         Section 7.5                Limitation on Guaranties................ 58
         Section 7.6                Investments and Acquisitions............ 59
         Section 7.7                Restricted Payments..................... 60
         Section 7.8                Leverage Ratio.......................... 60
         Section 7.9                Interest Coverage Ratio................. 61
         Section 7.10               Annualized Operating Cash Flow to Pro
                                    Forma Debt Service...................... 61
         Section 7.11               Limitation on Capital Expenditures...... 61
         Section 7.12               Affiliate Transactions.................. 62
         Section 7.13               Real Estate............................. 62
         Section 7.14               ERISA Liabilities....................... 62



                                      -ii-


<PAGE>


                                                                            Page


ARTICLE 8         Default................................................... 63

         Section 8.1                Events of Default....................... 63
         Section 8.2                Remedies................................ 66
         Section 8.3                Payments Subsequent to Declaration of
                                    Event of Default........................ 68

ARTICLE 9         The Administrative Agent.................................. 69

         Section 9.1                Appointment and Authorization........... 69
         Section 9.2                Interest Holders........................ 69
         Section 9.3                Consultation with Counsel............... 69
         Section 9.4                Documents............................... 69
         Section 9.5                Administrative Agent and Affiliates..... 70
         Section 9.6                Responsibility of the Administrative
                                    Agent................................... 70
         Section 9.7                Action by the Administrative Agent...... 70
         Section 9.8                Notice of Default or Event of Default... 71
         Section 9.9                Responsibility Disclaimed............... 72
         Section 9.10               Indemnification......................... 72
         Section 9.11               Credit Decision......................... 73
         Section 9.12               Successor Administrative Agent.......... 73
         Section 9.13               Delegation of Duties.................... 74

ARTICLE 10                 Change in Circumstances Affecting LIBOR
                           Advances......................................... 74

         Section 10.1               LIBOR Basis Determination Inadequate or
                                    Unfair.................................. 74
         Section 10.2               Illegality.............................. 74
         Section 10.3               Increased Costs......................... 75
         Section 10.4               Effect On Other Advances................ 76

ARTICLE 11                 Miscellaneous.................................... 77

         Section 11.1               Notices................................. 77
         Section 11.2               Expenses................................ 78
         Section 11.3               Waivers................................. 79
         Section 11.4               Set-Off................................. 79
         Section 11.5               Assignment.............................. 80
         Section 11.6               Accounting Principles................... 82
         Section 11.7               Counterparts............................ 83
         Section 11.8               Governing Law........................... 83
         Section 11.9               Severability............................ 84
         Section 11.10              Interest................................ 84
         Section 11.11              Table of Contents and Headings.......... 84
         Section 11.12              Amendment and Waiver.................... 84
         Section 11.13              Entire Agreement........................ 85


                                      -iii-


<PAGE>

                                                                            Page

         Section 11.14              Other Relationships..................... 85
         Section 11.15              Directly or Indirectly.................. 85
         Section 11.16              Reliance on and Survival of Various
                                    Provisions.............................. 86
         Section 11.17              Senior Debt............................. 86
         Section 11.18              Obligations Several..................... 86
         Section 11.19              Confidentiality......................... 86
         Section 11.20              Termination of Agreement................ 87

ARTICLE 12                 Waiver of Jury Trial............................. 87

         Section 12.1               Waiver of Jury Trial.................... 87



                                      -iv-


<PAGE>



                                    EXHIBITS


Exhibit  A                 -        Form of Borrower's Pledge Agreement
Exhibit  B                 -        Form of Borrower's Security Agreement
Exhibit  C                 -        Form of Certificate of Financial Condition
Exhibit  D                 -        Form of Promissory Note
Exhibit  E                 -        Form of Parent Pledge Agreement
Exhibit  F                 -        Form of Request for Advance
Exhibit  G                 -        Form of Subsidiary Guaranty
Exhibit  H                 -        Form of Subsidiary Pledge Agreement
Exhibit  I                 -        Form of Subsidiary Security Agreement
Exhibit  J                 -        Form of Use of Proceeds Letter
Exhibit  K                 -        Form of Borrower's Loan Certificate
Exhibit  L                 -        Form of Subsidiary Loan Certificate
Exhibit  M                 -        Form of Performance Certificate
Exhibit  N                 -        Form of Assignment and Assumption Agreement


                                    SCHEDULES


Schedule 1                          Licenses
Schedule 2                          Description of Philadelphia Disposition
Schedule 3                          List of Unrestricted Subsidiaries on the
                                    Agreement Date
Schedule 4.1(a)                     Exceptions to Representations and Warranties
Schedule 4.1(c)                     Subsidiaries
Schedule 4.1(i)                     Litigation
Schedule 4.1(s)                     Affiliate Transactions
Schedule 4.1(v)                     Indebtedness




                                       -v-


<PAGE>



                                 LOAN AGREEMENT
                                      AMONG
                 AMERICAN TOWER SYSTEMS, INC. (THE "BORROWER");
            THE FINANCIAL INSTITUTIONS WHOSE NAMES APPEAR AS BANKS ON
             THE SIGNATURE PAGES HEREOF (COLLECTIVELY, THE "BANKS");
                                       AND
                         TORONTO DOMINION (TEXAS), INC.,
                             AS ADMINISTRATIVE AGENT
                   FOR THE BANKS (THE "ADMINISTRATIVE AGENT")


                              W I T N E S S E T H:

         WHEREAS,  Borrower  has  requested  that the Banks  make  available  to
Borrower a revolving credit facility permitting advances of up to Ninety Million
Dollars ($90,000,000) at any one time outstanding; and

         WHEREAS,  the Banks are  willing to extend such  financing  to Borrower
subject to the terms and conditions set forth herein;

         NOW,  THEREFORE,  in  consideration  of the foregoing  premises and for
other good and valuable consideration,  the receipt, adequacy and sufficiency of
which are acknowledged by the parties hereto, it is hereby agreed as follows:


                                    ARTICLE 1

                                   Definitions

         For the purposes of this Agreement:

         "Acquisition"  shall  mean  (whether  by  purchase,   lease,  exchange,
issuance of stock or other equity or debt securities,  merger, reorganization or
any  other  method)  (i)  any  acquisition  by the  Borrower  or any  Restricted
Subsidiary of any other Person, which Person shall then become consolidated with
the Borrower or any such Restricted Subsidiary in accordance with GAAP; (ii) any
acquisition  by  the  Borrower  or  any  Restricted  Subsidiary  of  all  or any
substantial part of the assets of any other Person;  or (iii) any acquisition by
Borrower or any Restricted  Subsidiary of any  communications  tower facilities,
communications tower management businesses or related contracts,  other than any
such Acquisition which shall be made by, or of, any Person which shall have been
designated and approved as an Unrestricted Subsidiary.

         "Acquisition  Operating  Cash  Flow"  shall  mean  in  the  case  of an
Acquisition  permitted  hereunder,  Operating  Cash Flow of the Borrower and its
Restricted  Subsidiaries  for the period during which such  Acquisition  occurs,
adjusted  (A) to give effect to such  Acquisition,  as if such  Acquisition  had
occurred on the



<PAGE>



first  day of  such  period,  by  excluding  the  Operating  Cash  Flow  of such
Acquisition  during such period prior to the date of such Acquisition and adding
to the Operating Cash Flow of the Borrower,  if positive,  or  subtracting  from
such Operating Cash Flow, if negative,  the product of (i) the actual  Operating
Cash Flow of such  Acquisition  for that portion of such period from the date of
such  Acquisition to the last day of such period,  multiplied by (ii) a fraction
the  numerator  of which is the number of  calendar  days in such period and the
denominator of which is the number of days in such period from and including the
date of such Acquisition through the last day of such period.

         "Administrative  Agent" shall mean Toronto Dominion  (Texas),  Inc., in
its  capacity  as   Administrative   Agent  for  the  Banks  or  any   successor
Administrative Agent appointed pursuant to Section 9.12 hereof.

         "Administrative   Agent's   Office"   shall  mean  the  office  of  the
Administrative  Agent located at 909 Fannin  Street,  Suite 1700,  Houston Texas
77010,  or such other office as may be designated  pursuant to the provisions of
Section 11.1 hereof.

         "Advance"  shall mean  amounts  advanced  by the Banks to the  Borrower
pursuant  to Article 2 hereof on the  occasion of any  borrowing  and having the
same Interest Rate Basis and Interest  Period;  and  "Advances"  shall mean more
than one Advance.

         "Affiliate"  shall mean,  with  respect to a Person,  any other  Person
directly or indirectly controlling, controlled by, or under common control with,
such first Person.  For purposes of this  definition,  "control"  when used with
respect to any  Person  includes,  without  limitation,  the direct or  indirect
beneficial  ownership of more than ten percent (10%) of the voting securities or
voting  equity of such Person or the power to direct or cause the  direction  of
the management and policies of such Person whether by contract or otherwise. For
purposes of this Agreement,  American Radio Systems and its Affiliates  shall be
deemed to be Affiliates of the Borrower.

         "Agreement" shall mean this Loan Agreement,  as amended,  supplemented,
restated or otherwise modified from time to time.

         "Agreement Date" shall mean November 22, 1996.

         "American Radio Systems" shall mean American Radio Systems
Corporation, a Delaware corporation.

         "Annualized Operating Cash Flow" (a) for any calculation date up to and
including  December 31,  1997,  the product of (i)  Operating  Cash Flow for the
calendar  month-end being tested or the most recently  completed  calendar month
immediately preceding


                                       -2-


<PAGE>



the  calculation  date, as the case may be, times (ii) twelve (12);  and (b) for
any calculation  date after December 31, 1997, the product of (i) Operating Cash
Flow for the fiscal  quarter-end  being  tested or the most  recently  completed
fiscal quarter  immediately  preceding the calculation date, as the case may be,
times (ii) four (4).

         "Applicable  Law" shall mean, in respect of any Person,  all provisions
of constitutions, statutes, rules, regulations and orders of governmental bodies
or regulatory  agencies applicable to such Person,  including,  without limiting
the foregoing,  the Licenses,  the Communications Act, zoning ordinances and all
Environmental  Laws,  and all orders,  decisions,  judgments  and decrees of all
courts and arbitrators in proceedings or actions to which the Person in question
is a party or by which it is bound.

         "Applicable  Margin" shall mean the interest rate margin  applicable to
Base  Rate  Advances  and  LIBOR  Advances,  as the  case may be,  in each  case
determined in accordance with Section 2.3(f) hereof.

         "Applicable  Margin Ratio" shall mean, as of any date, the ratio of (a)
the Total Debt of the Borrower and its Restricted Subsidiaries on a consolidated
basis on such date to (b) the product of (i) Operating Cash Flow of the Borrower
and its Restricted Subsidiaries,  for the most recently completed fiscal quarter
times (ii) four (4).

         "Authorized  Signatory" shall mean such senior personnel of a Person as
may be duly  authorized  and  designated  in writing  by such  Person to execute
documents, agreements and instruments on behalf of such Person.

         "Available  Commitment" shall mean (a) prior to receipt by the Borrower
after the Agreement Date of not less than  $3,000,000.00 of contributed  equity,
and after giving effect to reductions  in the  Commitment  under Section 2.5 and
Section  2.6  hereof and  repayments  of the Loans  under  Section  2.7  hereof,
$70,000,000,  and (b)  thereafter,  after  giving  effect to  reductions  in the
Commitment  under Section 2.5 and Section 2.6 hereof and repayments of the Loans
under Section 2.7 hereof,  the lesser of (i) the Commitment and (ii) the maximum
amount of the Loans that could be  outstanding  hereunder  on such date  without
resulting in a breach of Section 7.8 or Section 7.10 hereof.

         "Banks"  shall mean the Persons  whose  names  appear as "Banks" on the
signature  pages hereof and any other Person  which  becomes a "Bank"  hereunder
after the Agreement Date; and "Bank" shall mean any one of the foregoing Banks.



                                       -3-


<PAGE>



         "Base Rate" shall mean,  at any time, a  fluctuating  interest rate per
annum equal to the higher of (a) the rate of  interest  quoted from time to time
by the  Administrative  Agent as its  "prime  rate"  or  "base  rate" or (b) the
Federal  Funds Rate plus  one-half of one percent  (1/2%).  The Base Rate is not
necessarily the lowest rate of interest charged by the  Administrative  Agent in
connection with extensions of credit.

         "Base Rate Advance"  shall mean an Advance which the Borrower  requests
to be made as a Base Rate Advance or is reborrowed  as a Base Rate  Advance,  in
accordance  with the  provisions of Section 2.2 hereof,  and which shall be in a
principal  amount  of at  least  $1,000,000,  and  in an  integral  multiple  of
$500,000.

         "Base Rate Basis" shall mean a simple interest rate equal to the sum of
(i) the Base  Rate  and  (ii) the  Applicable  Margin  applicable  to Base  Rate
Advances.  The Base Rate Basis shall be adjusted automatically as of the opening
of business on the effective date of each change in the Base Rate to account for
such  change,  and shall also be adjusted to reflect  changes of the  Applicable
Margin applicable to Base Rate Advances.

         "Borrower" shall mean American Tower Systems, Inc., a
Delaware corporation.

         "Borrower's Pledge Agreement" shall mean that certain Borrower's Pledge
Agreement  dated  as  of  even  date  herewith  between  the  Borrower  and  the
Administrative  Agent,  substantially  in the form of Exhibit A attached hereto,
pursuant to which the Borrower has pledged to the  Administrative  Agent for the
ratable benefit of the Banks all of the Borrower's  stock  ownership  and/or any
partnership interests in each of its Subsidiaries.

         "Borrower's  Security  Agreement"  shall  mean  that  certain  Security
Agreement  dated as of even date herewith,  made by the Borrower in favor of the
Administrative Agent for the ratable benefit of the Banks,  substantially in the
form of Exhibit B attached hereto.

         "Business  Day" shall mean a day on which  banks and  foreign  exchange
markets are open for the transaction of business  required for this Agreement in
Houston,  Texas,  New York,  New York and  London,  England,  as relevant to the
determination to be made or the action to be taken.

         "Capital  Expenditures"  shall  mean,  for  any  period,   expenditures
(including the aggregate amount of Capitalized Lease Obligations  required to be
paid during such period)  incurred by any Person to acquire or  construct  fixed
assets, plant and equipment (including renewals,  improvements and replacements,
but excluding repairs and maintenance) during such period, which


                                       -4-


<PAGE>



would be  required  to be  capitalized  on the  balance  sheet of such Person in
accordance with GAAP.

         "Capital Stock" shall mean, as applied to any Person, any capital stock
of such Person, regardless of class or designation,  and all warrants,  options,
purchase rights,  conversion or exchange rights,  voting rights, calls or claims
of any character with respect thereto.

         "Capitalized   Lease   Obligation"  shall  mean  that  portion  of  any
obligation  of a Person  as  lessee  under a lease  which  at the time  would be
required to be  capitalized  on the balance  sheet of such lessee in  accordance
with GAAP.

         "Certificate  of  Financial   Condition"   shall  mean  a  certificate,
substantially  in the form of  Exhibit C  attached  hereto,  signed by the chief
financial  officer of the  Borrower,  together with any  schedules,  exhibits or
annexes appended thereto.

         "Change of Control" shall mean, as applied to the Borrower,  any change
in the ownership of, or lien upon, the stock of the Borrower that results in (a)
less than  fifty-one  percent  (51%) of all voting  rights  with  respect to the
Capital Stock of the Borrower (including, without limitation, warrants, options,
conversion  rights,  voting  rights  and calls or claims of any  character  with
respect  thereto,  to the extent  exercisable  prior to repayment in full of the
Obligations)  being owned,  directly or  indirectly,  by the Parent,  the senior
management  of  American  Radio  Systems,  the  Parent  and/or the  Borrower  or
Affiliates of American Radio Systems, the Parent or the Borrower or (b) American
Radio  Systems  having no direct or indirect  ownership  interest in the Capital
Stock of the Borrower.

         "Code"  shall mean the Internal  Revenue Code of 1986,  as amended from
time to time.

         "Collateral"   shall  mean  any  property  of  any  kind   constituting
collateral for the Obligations under any of the Security Documents.

         "Commitment"  shall mean the several  obligations  of the Banks to fund
their  respective  portion of the Loans to the Borrower in accordance with their
respective Commitment Ratios in the aggregate sum of up to $90,000,000, pursuant
to the  terms  hereof,  as such  obligations  may be  reduced  from time to time
pursuant to the terms hereof.

         "Commitment Ratios" shall mean the percentages in which the
Banks are severally bound to fund their respective portion of


                                       -5-


<PAGE>



Advances  to the  Borrower  under the  Commitment,  which  are set  forth  below
(together with dollar amounts) as of the Agreement Date:

           Bank                      Approximate                     Dollar
                                     Percentage                    Commitment
                                     ----------                    ----------
Toronto Dominion (Texas), Inc.      22.22222222%                 $20,000,000.00
Banque Paribas                      16.66666667%                 $15,000,000.00
Bank of Montreal                    13.33333333%                 $12,000,000.00
Credit Suisse                       13.33333333%                 $12,000,000.00
Union Bank of California, N.A.      13.33333333%                 $12,000,000.00
Signet Bank                         10.55555556%                  $9,500,000.00
Fleet National Bank                 10.55555556%                  $9,500,000.00
                                    ============                 ==============

                                       100.00%                   $90,000,000.00


         "Communications Act" shall mean the Communications Act of 1934, and any
similar or successor  federal statute,  and the rules and regulations of the FCC
thereunder, all as the same may be in effect from time to time.

         "Default"  shall  mean any  Event  of  Default,  and any of the  events
specified in Section 8.1 hereof, regardless of whether there shall have occurred
any passage of time or giving of notice,  or both,  that would be  necessary  in
order to constitute such event an Event of Default.

         "Default Rate" shall mean a simple per annum interest rate equal to the
sum of (a) the Base Rate, plus (b) the Applicable  Margin for Base Rate Advances
plus (c) two percent (2%).

         "Employee  Pension Plan" shall mean any Plan which is maintained by the
Borrower, any of its Subsidiaries or any ERISA Affiliate.

         "Environmental Laws" shall mean all applicable federal,  state or local
laws,  statutes,  rules,  regulations or ordinances,  codes, common law, consent
agreements,  orders,  decrees,  judgments or  injunctions  issued,  promulgated,
approved  or  entered  thereunder  relating  to  public  health,  safety  or the
pollution or protection of the environment, including, without limitation, those
relating to releases,  discharges,  emissions, spills, leaching, or disposals to
air,  water,  land or ground water, to the withdrawal or use of ground water, to
the use,  handling or disposal of  polychlorinated  biphenyls,  asbestos or urea
formaldehyde,  to the  treatment,  storage,  disposal or management of hazardous
substances (including, without limitation,  petroleum, crude oil or any fraction
thereof,  or other  hydrocarbons),  pollutants or  contaminants,  to exposure to
toxic,


                                       -6-


<PAGE>



hazardous or other controlled,  prohibited, or regulated substances,  including,
without  limitation,  any such provisions under the Comprehensive  Environmental
Response, Compensation and Liability Act of 1980, as amended (42 U.S.C. ss. 9601
et seq.), or the Resource Conservation and Recovery Act of 1976, as amended
(42 U.S.C. ss. 6901 et seq.).

         "ERISA" shall mean the Employee Retirement Income Security Act of 1974,
as in effect from time to time.

         "ERISA  Affiliate" shall mean any Person,  including a Subsidiary or an
Affiliate of the  Borrower,  that is a member of any group of  organizations  of
which the Borrower is a member and which is covered by a Plan.

         "Eurodollar  Reserve  Percentage" shall mean the percentage which is in
effect from time to time under  Regulation  D of the Board of  Governors  of the
Federal Reserve System,  as such regulation may be amended from time to time, as
the  maximum  reserve  requirement   applicable  with  respect  to  Eurocurrency
Liabilities  (as that term is defined in Regulation  D), whether or not any Bank
has any such  Eurocurrency  Liabilities  subject to such reserve  requirement at
that time.

         "Event of Default"  shall mean any of the events  specified  in Section
8.1 hereof,  provided that any requirement for notice or lapse of time, or both,
has been satisfied.

         "Excess Cash Flow" shall mean,  as of the end of any fiscal year of the
Borrower based on the audited  financial  statements  provided under Section 6.2
hereof for such fiscal year, the excess,  if any, of (a) Operating Cash Flow for
such fiscal year,  minus (b) the sum of the  following:  (i) payments  made with
respect to Capital  Expenditures  incurred by the  Borrower  and its  Restricted
Subsidiaries  during such fiscal year;  (ii)  repayments of the Loans  resulting
from reductions of the Commitment  (which shall include any reductions set forth
in  Section  2.5(a)  hereof);  (iii) cash  taxes  paid by the  Borrower  and its
Restricted  Subsidiaries  (including any paid to American Radio Systems pursuant
to the Tax Sharing  Agreement)  during such fiscal year;  (iv) Interest  Expense
during  such  fiscal  year;  and  (v)  principal  payments  made in  respect  of
Indebtedness  for Money Borrowed  (other than with respect to the Loans) paid by
the Borrower and its Restricted Subsidiaries during such fiscal year.

         "FCC" shall mean the Federal  Communications  Commission,  or any other
similar  or  successor  agency  of  the  federal  government  administering  the
Communications Act.

         "Federal Funds Rate" shall mean, as of any date, the
weighted average of the rates on overnight federal funds


                                       -7-


<PAGE>



transactions  with the members of the Federal Reserve System arranged by federal
funds brokers, as published for such day (or, if such day is not a Business Day,
for the next  preceding  Business Day) by the Federal  Reserve Bank of New York,
or, if such rate is not so  published  for any day which is a Business  Day, the
average of the  quotations  for such day on such  transactions  received  by the
Administrative Agent from three (3) federal funds brokers of recognized standing
selected by the Administrative Agent.

         "GAAP" shall mean, as in effect from time to time,  generally  accepted
accounting principles in the United States, consistently applied.

         "Guaranty" or "Guaranteed," as applied to an obligation, shall mean and
include (a) a guaranty, direct or indirect, in any manner, of all or any part of
such  obligation,  and (b) any  agreement,  direct or  indirect,  contingent  or
otherwise,  the practical effect of which is to assure in any way the payment or
performance  (or payment of damages in the event of  non-performance)  of all or
any part of such  obligation,  including,  without  limiting the foregoing,  any
reimbursement   obligations  as  to  amounts  drawn  down  by  beneficiaries  of
outstanding letters of credit or capital call requirements.

         "Indebtedness"  shall mean,  with  respect to any  Person,  and without
duplication,  (a) all items,  except items of shareholders' and partners' equity
or capital  stock or surplus or general  contingency  or deferred tax  reserves,
which in accordance with GAAP would be included in determining total liabilities
as shown on the  liability  side of a balance  sheet of such Person,  including,
without limitation, with respect to any secured non-recourse obligations of such
Person,  the higher of the book value or fair  market  value of the  property or
asset securing such obligation (if less than the amount of such obligation), (b)
all direct or indirect  obligations  of any other Person  secured by any Lien to
which any  property or asset  owned by such  Person is subject,  but only to the
extent of the higher of the fair market  value or the book value of the property
or asset subject to such Lien (if less than the amount of such  obligation),  if
the obligation  secured  thereby shall not have been assumed,  (c) to the extent
not otherwise included, all Capitalized Lease Obligations of such Person and all
obligations  of such Person with respect to leases  constituting  part of a sale
and lease-back  arrangement,  (d) all reimbursement  obligations with respect to
outstanding letters of credit, and (e) to the extent not otherwise included, all
obligations  subject to Guaranties of such Person or its  Subsidiaries,  and (f)
all obligations of such Person under Interest Hedge Agreements.



                                       -8-


<PAGE>



         "Indebtedness  for Money  Borrowed"  shall  mean,  with  respect to any
Person,  Indebtedness for money borrowed and  Indebtedness  represented by notes
payable and drafts accepted  representing  extensions of credit, all obligations
evidenced  by  bonds,  debentures,  notes  or  other  similar  instruments,  all
Indebtedness  upon which interest charges are customarily paid (other than trade
payables arising in the ordinary course of business,  but only if and so long as
such  accounts are payable on customary  trade  terms),  all  Capitalized  Lease
Obligations,  all reimbursement  obligations with respect to outstanding letters
of credit,  all  Indebtedness  issued or assumed as full or partial  payment for
property or services  (other than trade payables  arising in the ordinary course
of business,  but only if and so long as such  accounts are payable on customary
trade terms), whether or not any such notes, drafts, obligations or Indebtedness
represent Indebtedness for money borrowed, and, without duplication,  Guaranties
of any of the  foregoing.  For purposes of this  definition,  interest  which is
accrued but not paid on the scheduled due date for such interest shall be deemed
Indebtedness for Money Borrowed.

         "Indemnitee" shall have the meaning ascribed thereto in
Section 5.12 hereof.

         "Interest  Coverage Ratio" shall mean, for any period, the ratio of (a)
Annualized  Operating Cash Flow as of (i) the calendar quarter end being tested,
or (ii) the most recently completed calendar quarter, as the case may be, to (b)
Interest Expense for (i) the four (4) calendar quarter period then ended or (ii)
the most recently  completed four (4) calendar  quarter period,  as the case may
be, in each case calculated in accordance with GAAP.

         "Interest  Expense"  shall  mean,  for any  period,  all cash  interest
expense   (including   imputed  interest  with  respect  to  Capitalized   Lease
Obligations) with respect to any Indebtedness for Money Borrowed of the Borrower
and its  Restricted  Subsidiaries  on a  consolidated  basis  during such period
pursuant to the terms of such Indebtedness for Money Borrowed, together with all
fees payable in respect thereof, all as calculated in accordance with GAAP.

         "Interest  Hedge  Agreements"  shall mean the obligations of any Person
pursuant  to  any  arrangement  with  any  other  Person  whereby,  directly  or
indirectly,  such  Person is  entitled  to  receive  from time to time  periodic
payments calculated by applying either a floating or a fixed rate of interest on
a stated notional  amount in exchange for periodic  payments made by such Person
calculated  by  applying  a fixed or a  floating  rate of  interest  on the same
notional amount and shall include, without


                                       -9-


<PAGE>



limitation, interest rate swaps, caps, floors, collars and
similar agreements.

         "Interest  Period"  shall  mean (a) in  connection  with any Base  Rate
Advance, the period beginning on the date such Advance is made and ending on the
last day of the  calendar  quarter  in which  such  Advance  is made,  provided,
however,  that if a Base Rate  Advance  is made on the last day of any  calendar
quarter,  it shall have an Interest Period ending on, and its Payment Date shall
be, the last day of the following  calendar quarter,  and (b) in connection with
any  LIBOR  Advance,  the  term of such  Advance  selected  by the  Borrower  or
otherwise  determined in accordance  with this  Agreement.  Notwithstanding  the
foregoing, however, (i) any applicable Interest Period which would otherwise end
on a day which is not a Business  Day shall be extended  to the next  succeeding
Business Day unless,  with respect to LIBOR  Advances  only,  such  Business Day
falls in another calendar month, in which case such Interest Period shall end on
the next  preceding  Business Day, (ii) any  applicable  Interest  Period,  with
respect to LIBOR  Advances  only,  which  begins on a day for which  there is no
numerically  corresponding  day in the calendar month during which such Interest
Period is to end shall (subject to clause (i) above) end on the last day of such
calendar month, and (iii) the Borrower shall not select an Interest Period which
extends  beyond the Maturity Date or such earlier date as would  interfere  with
the Borrower's  repayment  obligations under Section 2.5, Section 2.6 or Section
2.7 hereof.  Interest  shall be due and payable  with  respect to any Advance as
provided in Section 2.3 hereof.

         "Interest  Rate  Basis"  shall  mean the Base  Rate  Basis or the LIBOR
Basis, as appropriate.

         "known to the  Borrower" or "to the  knowledge of the  Borrower"  shall
mean known by or reasonably should have been known by the executive  officers of
the Borrower  (which shall  include,  without  limitation,  the chief  executive
officer,  the chief operating  officer,  if any, the chief financial officer and
the general counsel, or any vice president of the Borrower).

         "Leasing  Operating  Expenses"  shall mean,  for any period,  operating
expenses for such period  attributable to the leasing operations of the Borrower
and its  Restricted  Subsidiaries  based  upon the ratio of the  number of sites
owned or leased by the Borrower  and its  Restricted  Subsidiaries  to the total
number of all sites owned, leased and managed by the Borrower and its Restricted
Subsidiaries.

         "Leasing  Overhead"  shall  mean,  for any period,  corporate  overhead
(exclusive  of  amortization  and  depreciation)  attributable  to  the  leasing
operations of the Borrower and its Restricted Subsidiaries for such period based
upon the ratio of


                                      -10-


<PAGE>



the  number  of  sites  owned  or  leased  by the  Borrower  and its  Restricted
Subsidiaries to the total of all sites owned, leased and managed by the Borrower
and its Restricted Subsidiaries.

         "Leverage Ratio" shall mean, as of any date, the ratio of (a) the Total
Debt of the Borrower and its Restricted  Subsidiaries on a consolidated basis on
such  date,  to (b)  Annualized  Operating  Cash  Flow of the  Borrower  and its
Restricted Subsidiaries on a consolidated basis for (x) all periods ending prior
to January 1, 1998,  the calendar  month end being  tested or the most  recently
completed  calendar  month,  as the  case  may be and  (y)  all  periods  ending
thereafter, the calendar quarter end being tested or the most recently completed
calendar quarter, as the case may be.

         "LIBOR"  shall  mean,  for any  Interest  Period,  the  average  of the
interest  rates per annum at which  deposits in United  States  Dollars for such
Interest Period are offered to the Administrative Agent in the Eurodollar market
at approximately 11:00 a.m. (London time) two (2) Business Days before the first
day of such Interest Period, in an amount  approximately  equal to the principal
amount of, and for a length of time  approximately  equal to the Interest Period
for, the LIBOR Advance sought by the Borrower.

         "LIBOR Advance" shall mean an Advance which the Borrower requests to be
made as a LIBOR Advance or which is reborrowed as a LIBOR Advance, in accordance
with the  provisions  of Section 2.2  hereof,  and which shall be in a principal
amount of at least $5,000,000 and in an integral multiple of $1,000,000.

         "LIBOR  Basis"  shall mean a simple per annum  interest  rate  (rounded
upward,  if necessary,  to the nearest  one-hundredth  (1/100th) of one percent)
equal to the sum of (a) the quotient of (i) the LIBOR  divided by (ii) one minus
the Eurodollar  Reserve  Percentage,  if any, stated as a decimal,  plus (b) the
Applicable  Margin.  The LIBOR Basis shall apply to Interest Periods of one (1),
two (2),  three (3), or six (6)  months,  and,  once  determined,  shall  remain
unchanged during the applicable  Interest Period,  except for changes to reflect
adjustments in the Eurodollar  Reserve  Percentage and the Applicable  Margin as
adjusted  pursuant  to  Section  2.3(f)  hereof.  The LIBOR  Basis for any LIBOR
Advance  shall  be  adjusted  as of the  effective  date  of any  change  in the
Eurodollar Reserve Percentage.

         "Licenses" shall mean any telephone,  microwave,  radio  transmissions,
personal  communications  or  other  license,   authorization,   certificate  of
compliance,  franchise,  approval or permit,  whether for the construction,  the
ownership or the operation of any  communications  tower facilities,  granted or
issued by the FCC and held by the Borrower or any of its


                                      -11-


<PAGE>



Restricted  Subsidiaries,  all of which as of the  Agreement  Date are listed on
Schedule 1 attached hereto.

         "Lien" shall mean,  with respect to any property,  any mortgage,  lien,
pledge,  negative pledge or other agreement not to pledge,  assignment,  charge,
security  interest,  title  retention  agreement,   levy,  execution,   seizure,
attachment,  garnishment  or other  encumbrance  of any kind in  respect of such
property, whether created by statute, contract, the common law or otherwise, and
whether or not choate, vested or perfected.

         "Loan Documents"  shall mean this Agreement,  the Notes, the Borrower's
Pledge Agreement,  the Borrower's  Security  Agreement,  the Subsidiary Security
Agreement,  the Subsidiary Guaranty, the Subsidiary Pledge Agreement, the Parent
Pledge Agreement,  all fee letters, all Requests for Advance, all Interest Hedge
Agreements between the Borrower,  on the one hand, and the Administrative  Agent
and the Banks,  or any of them, on the other hand,  and all other  documents and
agreements executed or delivered by the Borrower or its Restricted  Subsidiaries
in connection with or contemplated by this Agreement.

         "Loans" shall mean, collectively,  the amounts advanced by the Banks to
the Borrower under the Commitment,  not to exceed the Commitment,  and evidenced
by the Notes.

         "Majority  Banks"  shall  mean  (i) at  any  time  that  no  Loans  are
outstanding  hereunder,  Banks the total of whose  Commitment  Ratios  equals or
exceeds sixty percent (60%) of the  Commitment  Ratios of all Banks  entitled to
vote hereunder,  or (ii) at any time that there are Loans outstanding hereunder,
Banks the total of whose Loans outstanding equals or exceeds sixty percent (60%)
of the  total  principal  amount  of the  Loans  then  outstanding  of all Banks
entitled to vote hereunder.

         "Management  Operating Expenses" shall mean, for any period,  operating
expenses  attributable  to the  management  operations  of the  Borrower and its
Restricted  Subsidiaries  for such period  based upon the ratio of the number of
sites  managed by the  Borrower  and its  Restricted  Subsidiaries  to the total
number of all sites owned, leased and managed by the Borrower and its Restricted
Subsidiaries.

         "Management  Overhead" shall mean, for any period,  corporate  overhead
(exclusive of  amortization  and  depreciation)  attributable  to the management
operations of the Borrower and its Restricted  Subsidiaries based upon the ratio
of the number of sites managed by the Borrower and its  Restricted  Subsidiaries
to the total number of all sites  owned,  leased and managed by the Borrower and
its Restricted Subsidiaries.



                                      -12-


<PAGE>



         "Materially  Adverse Effect" shall mean (a) any material adverse effect
upon the business, assets, business prospects, liabilities, financial condition,
results  of  operations  or  properties  of  the  Borrower  and  its  Restricted
Subsidiaries  on a  consolidated  basis,  taken  as a whole,  or (b) a  material
adverse effect upon the binding  nature,  validity,  or  enforceability  of this
Agreement and the Notes,  or upon the ability of the Borrower and its Restricted
Subsidiaries  to perform the payment  obligations or other material  obligations
under  this  Agreement  or any  other  Loan  Document,  or upon the value of the
Collateral or upon the rights,  benefits or interests of the Banks in and to the
Loans or the rights of the Administrative Agent and the Banks in the Collateral;
in either case,  whether  resulting  from any single act,  omission,  situation,
status, event or undertaking, or taken together with other such acts, omissions,
situations, statuses, events or undertakings.

         "Maturity  Date" shall mean December 31, 2004,  or, as the case may be,
such  earlier  date as  payment  of the  Obligations  shall be due  (whether  by
acceleration, reduction of the Commitment to zero or otherwise).

         "Multiemployer Plan" shall mean a multiemployer pension plan as defined
in Section 3(37) of ERISA to which the Borrower,  any of its Subsidiaries or any
ERISA Affiliate is or has been required to contribute.

         "Necessary  Authorizations" shall mean all approvals and licenses from,
and all filings and  registrations  with, any  governmental or other  regulatory
authority,  including,  without  limiting  the  foregoing,  the Licenses and all
approvals,  licenses,  filings and registrations  under the Communications  Act,
necessary  in order to enable the Borrower and its  Restricted  Subsidiaries  to
own, construct,  maintain,  and operate  communications  tower facilities and to
invest  in other  Persons  who own,  construct,  maintain,  manage  and  operate
communications tower facilities.

         "Net  Income"  shall  mean,   for  the  Borrower  and  its   Restricted
Subsidiaries on a consolidated  basis, for any period,  net income determined in
accordance with GAAP.

         "Net Proceeds" shall mean, with respect to any sale, lease, transfer or
other   disposition  of  assets  by  the  Borrower  or  any  of  its  Restricted
Subsidiaries,  the aggregate amount of cash received for such assets (including,
without  limitation,   any  payments  received  for  non-competition  covenants,
consulting or management  fees in connection  with such sale, and any portion of
the  amount  received  evidenced  by a  promissory  note or  other  evidence  of
Indebtedness issued by the purchaser),  net of (i) amounts reserved, if any, for
taxes  payable  with  respect  to any such  sale  (after  application  (assuming
application first to


                                      -13-


<PAGE>



such  reserves)  of any  available  losses,  credits  or  other  offsets),  (ii)
reasonable  and  customary  transaction  costs  properly  attributable  to  such
transaction  and payable by the Borrower or any of its  Restricted  Subsidiaries
(other than to an Affiliate) in connection  with such sale,  lease,  transfer or
other disposition of assets,  including,  without limitation,  commissions,  and
(iii)  until  actually  received  by the  Borrower  or  any  of  its  Restricted
Subsidiaries,  any portion of the amount received held in escrow or evidenced by
a promissory  note or other  evidence of  Indebtedness  issued by a purchaser or
non-compete,  consulting  or  management  agreement or covenant or otherwise for
which compensation is paid over time. Upon receipt by the Borrower or any of its
Restricted  Subsidiaries  of  (A)  amounts  referred  to in  item  (iii)  of the
preceding  sentence,  or (B) if  there  shall  occur  any  reduction  in the tax
reserves  referred  to in item  (i) of the  preceding  sentence  resulting  in a
payment to the Borrower, such amounts shall then be deemed to be "Net Proceeds."

         "Notes" shall mean, collectively, those certain promissory notes in the
aggregate  original  principal amount of $90,000,000,  and issued to each of the
Banks by the Borrower,  each one substantially in the form of Exhibit D attached
hereto,  any other  promissory note issued by the Borrower to evidence the Loans
pursuant to this Agreement,  and any extensions,  renewals, or amendments to, or
replacements of, the foregoing.

         "Obligations"  shall mean all payment and  performance  obligations  of
every kind, nature and description of the Borrower, its Restricted Subsidiaries,
and any other  obligors to the Banks,  or the  Administrative  Agent,  or any of
them, under this Agreement and the other Loan Documents (including any interest,
fees and other charges on the Loans or otherwise  under the Loan  Documents that
would  accrue  but for the filing of a  bankruptcy  action  with  respect to the
Borrower,  whether or not such claim is  allowed in such  bankruptcy  action and
including  Obligations to the Banks pursuant to Section 5.13 hereof) as they may
be amended from time to time,  or as a result of making the Loans,  whether such
obligations  are direct or  indirect,  absolute or  contingent,  due or not due,
contractual or tortious, liquidated or unliquidated, arising by operation of law
or otherwise, now existing or hereafter arising.

         "Operating  Cash Flow" shall mean, (a) with respect to the Borrower and
its Restricted  Subsidiaries on a consolidated basis as of the end of any period
from the Agreement  Date through and including June 30, 1997, (i) the sum of (A)
operating  revenues of the Borrower  and its  Restricted  Subsidiaries  plus (B)
Unrestricted  Subsidiary  Distributions  during such period less (ii) the sum of
(A) operating expenses for such period plus (B) corporate overhead (exclusive of
amortization and depreciation)


                                      -14-


<PAGE>



for such  period;  and (b)  with  respect  to the  Borrower  and its  Restricted
Subsidiaries  on a  consolidated  basis as of the end of any period ending after
June 30, 1997, the sum of (i) (A) operating revenues from leasing operations for
such period minus (B) the sum of (1) Leasing Operating Expenses for such period,
and (2)  Leasing  Overhead  for such  period,  plus  (ii) the  lesser of (A) (1)
operating revenues from management  agreement  operations,  minus (2) the sum of
(x)  Management  Operating  Expenses and (y)  Management  Overhead  ("Management
Operations  Cash Flow") for such period and (B) ten percent  (10%) of the amount
calculated  under  clause  (b)(i) above for such period plus (iii) to the extent
that the total  amount of  Management  Operations  Cash Flow for such  period is
greater  than the amount  calculated  pursuant to clause  (b)(ii)  above,  fifty
percent  (50%)  of  such  excess  amount  plus  (iv)   Unrestricted   Subsidiary
Distributions  for such period.  In the case of determining  Operating Cash Flow
under Sections 2.3, 7.8, 7.9 and 7.10 hereof following an Acquisition  permitted
hereunder,  Operating Cash Flow of the Borrower and its Restricted  Subsidiaries
shall include the  Acquisition  Operating Cash Flow. For purposes of calculating
Operating Cash Flow in connection with any Advance for an Acquisition, Operating
Cash Flow for the Borrower and its Restricted Subsidiaries as of the last day of
the  immediately  preceding  calendar  quarter and/or calendar month end, as the
case may be, shall include  "operating  cash flow" for the  Acquisition  for the
same period after giving effect to adjustments  reasonably  satisfactory  to the
Administrative Agent.

         "Parent" shall mean American Tower Systems Holding
Corporation, a Delaware corporation.

         "Parent  Pledge  Agreement"  shall  mean  that  certain  Parent  Pledge
Agreement  dated  as of even  date  herewith,  made by  Parent  in  favor of the
Administrative Agent for the ratable benefit of the Banks,  substantially in the
form of Exhibit E attached hereto.

         "Payment Date" shall mean the last day of any Interest
Period.

         "PBGC" shall mean the Pension Benefit Guaranty Corporation,
or any successor thereto.

         "Permitted Liens" shall mean, as applied to any Person:

                  (a)      any Lien in favor of the Administrative Agent
given to secure the Obligations;

                  (b) (i) Liens on real  estate  or other  property  for  taxes,
assessments,  governmental  charges or levies not yet  delinquent and (ii) Liens
for taxes, assessments,  judgments, governmental charges or levies or claims the
non-payment of which


                                      -15-


<PAGE>



is being diligently  contested in good faith by appropriate  proceedings and for
which adequate  reserves have been set aside on such Person's books, but only so
long  as no  foreclosure,  distraint,  sale or  similar  proceedings  have  been
commenced with respect thereto;

                  (c)  Liens  of  carriers,  warehousemen,  mechanics,  vendors,
(solely to the extent  arising by  operation of law)  laborers  and  materialmen
incurred  in the  ordinary  course  of  business  for  sums not yet due or being
diligently contested in good faith, if reserves or appropriate  provisions shall
have been made therefor;

                  (d) Liens  incurred  in the  ordinary  course of  business  in
connection  with  worker's  compensation  and  unemployment  insurance,   social
security  obligations,  assessments or government  charges which are not overdue
for more than sixty (60) days;

                  (e)      restrictions on the transfer of the Licenses or
assets of the Borrower or its Restricted Subsidiaries imposed by
any of the Licenses as presently in effect or by the
Communications Act and any regulations thereunder;

                  (f) easements, rights-of-way,  zoning restrictions,  licenses,
reservations or restrictions on use and other similar encumbrances on the use of
real property which do not materially interfere with the ordinary conduct of the
business of such Person or the use of such property;

                  (g) liens  arising by operation of law in favor of  purchasers
in connection with any asset sale permitted  hereunder;  provided that such lien
only encumbers the property being sold.

                  (h) Liens  reflected  by  Uniform  Commercial  Code  financing
statements filed in respect of Capitalized Lease Obligations  permitted pursuant
to  Section  7.1  hereof  and  true  leases  of  the  Borrower  or  any  of  its
Subsidiaries;

                  (i)  Liens to secure  performance  of  statutory  obligations,
surety or appeal bonds,  performance  bonds, bids, tenders or escrow deposits in
connection with permitted Acquisitions;

                  (j)      judgment Liens which do not result in an Event of
Default under Section 8.1(h) hereof;

                  (k)      Liens in connection with escrow deposits made in
connection with Acquisitions permitted hereunder; and

                  (l)      additional Liens securing Indebtedness which does
not in the aggregate outstanding at any time exceed $500,000.


                                      -16-


<PAGE>




         "Person"  shall  mean an  individual,  corporation,  limited  liability
company,   association,   partnership,   joint  venture,  trust  or  estate,  an
unincorporated organization, a government or any agency or political subdivision
thereof, or any other entity.

         "Philadelphia  Disposition"  shall  mean  the sale by the  Borrower  of
certain  real  property   located  in   Philadelphia,   Pennsylvania   and  more
particularly described on Schedule 2 attached hereto.

         "Plan"  shall mean an  employee  benefit  plan  within  the  meaning of
Section  3(3) of  ERISA  or any  other  employee  benefit  plan  maintained  for
employees of any Person or any affiliate of such Person.

         "Pro Forma Debt  Service"  shall mean with  respect to the Borrower and
its Restricted  Subsidiaries,  on a consolidated basis, with respect to the next
succeeding complete twelve (12) month period following the calculation date, and
after giving effect to any Interest Hedge Agreements and LIBOR Advances, the sum
of the amount of all (i)  scheduled  payments of principal on  Indebtedness  for
Money  Borrowed  (determined  with respect to the Loans only, as the  difference
between the outstanding  principal  amount of the Loans on the calculation  date
and the amount the Commitment will be after the reductions  thereof set forth in
Section 2.5 hereof for such four calendar  quarter period have taken effect) for
such period,  (ii)  Interest  Expense for such period,  (iii) fees payable under
this Agreement for such period,  and (iv) other payments payable by such Persons
during such period in respect of  Indebtedness  for Money  Borrowed  (other than
voluntary repayments under Section 2.7 hereof). For purposes of this definition,
where interest payments for the twelve (12) month period immediately  succeeding
the calculation  date are not fixed by way of Interest Hedge  Agreements,  LIBOR
Advances,  or otherwise for the entire  period,  interest shall be calculated on
such Indebtedness for Money Borrowed for periods for which interest payments are
not so fixed at the  lesser of (a) the LIBOR  Basis  (based on the then  current
adjustment  under Section  2.3(f) hereof) for a LIBOR Advance having an Interest
Period of six (6) months as  determined on the date of  calculation  and (b) the
Base Rate Basis as in effect on the date of calculation; provided, however, that
if such  LIBOR  Basis  cannot be  determined  in the  reasonable  opinion of the
Administrative  Agent,  such interest  shall be  calculated  using the Base Rate
Basis as then in effect.

         "Reportable  Event" shall mean,  with  respect to any Employee  Pension
Plan, an event described in Section 4043(b) of ERISA.

         "Request for Advance" shall mean a certificate designated as a "Request
for Advance,"  signed by an Authorized  Signatory of the Borrower  requesting an
Advance hereunder, which shall be in


                                      -17-


<PAGE>



substantially  the form of Exhibit F attached  hereto,  and shall,  among  other
things, (i) specify the date of the Advance,  which shall be a Business Day, the
amount of the Advance,  the type of Advance (Eurodollar or Base Rate), and, with
respect to LIBOR Advances,  the Interest  Period selected by the Borrower,  (ii)
state that there shall not exist, on the date of the requested Advance and after
giving  effect  thereto,  a Default,  as of the date of such  Advance  and after
giving effect thereto, and (iii) the Applicable Margin then in effect.

         "Restricted  Payment"  shall mean any direct or indirect  distribution,
dividend  or other  payment to any Person  (other  than to the  Borrower  or any
Restricted  Subsidiary  of the  Borrower)  on account of any  general or limited
partnership  interest in, or shares of Capital Stock or other securities of, the
Borrower or any of its Restricted  Subsidiaries  (other than  dividends  payable
solely in stock of such Person and stock splits), including, without limitation,
any direct or indirect  distribution,  dividend  or other  payment to any Person
(other than to the Borrower or any  Restricted  Subsidiary  of the  Borrower) on
account of any warrants or other rights or options to acquire  shares of Capital
Stock of the Borrower or any of its Restricted Subsidiaries.

         "Restricted Subsidiary" shall mean any Subsidiary of the Borrower other
than an Unrestricted Subsidiary.

         "Security  Documents" shall mean the Borrower's Pledge  Agreement,  the
Subsidiary  Guaranty,  the Subsidiary Pledge Agreement,  the Borrower's Security
Agreement,  the Subsidiary Security Agreement,  the Parent Pledge Agreement, any
other agreement or instrument  providing  collateral for the Obligations whether
now or hereafter in existence,  and any filings,  instruments,  agreements,  and
documents related thereto or to this Agreement, and providing the Administrative
Agent, for the benefit of the Banks, with Collateral for the Obligations.

         "Security Interest" shall mean all Liens in favor of the Administrative
Agent,  for the  benefit of the  Banks,  created  hereunder  or under any of the
Security Documents to secure the Obligations.

         "Subsidiary"  shall mean, as applied to any Person, (a) any corporation
of which more than fifty  percent  (50%) of the  outstanding  stock  (other than
directors'  qualifying  shares) having ordinary voting power to elect a majority
of its board of directors, regardless of the existence at the time of a right of
the  holders  of any class or  classes  of  securities  of such  corporation  to
exercise such voting power by reason of the happening of any contingency, or any
partnership  of  which  more  than  fifty  percent  (50%)  of  the   outstanding
partnership interests, is at the time owned directly or indirectly by such


                                      -18-


<PAGE>



Person, or by one or more Subsidiaries of such Person, or by such Person and one
or more  Subsidiaries of such Person,  or (b) any other entity which is directly
or indirectly  controlled or capable of being  controlled by such Person,  or by
one or more  Subsidiaries  of such  Person,  or by such  Person  and one or more
Subsidiaries of such Person.

         "Subsidiary Guaranty" shall mean that certain Subsidiary Guaranty dated
as of even date herewith,  in favor of the  Administrative  Agent and the Banks,
given by each Restricted  Subsidiary of the Borrower,  substantially in the form
of Exhibit G hereof, and shall include any similar agreements  executed pursuant
to Section 5.14 hereof.

         "Subsidiary Pledge Agreement" shall mean that certain Subsidiary Pledge
Agreement dated as of even date herewith made by each  Restricted  Subsidiary of
the Borrower  having one or more of its own  Subsidiaries,  on the one hand,  in
favor of the Administrative Agent, on the other hand,  substantially in the form
of Exhibit H hereof, and shall include any similar agreements  executed pursuant
to Section 5.14 hereof.

         "Subsidiary  Security  Agreement"  shall mean that  certain  Subsidiary
Security Agreement dated as of even date herewith between each of the Borrower's
Restricted  Subsidiaries,  on the one hand, and the  Administrative  Agent,  (on
behalf of itself and the Banks), on the other hand, substantially in the form of
Exhibit I hereof, and shall include any similar agreements  executed pursuant to
Section 5.14 hereof.

         "Tax Sharing  Agreement" shall mean that certain Tax Sharing Agreement,
dated as of October 15, 1996, among Borrower, American Radio Systems and certain
other Subsidiaries of American Radio Systems.

         "Total  Debt"  shall  mean,   for  the  Borrower  and  its   Restricted
Subsidiaries  on  a  consolidated  basis  as  of  any  date,  the  sum  (without
duplication)  of (i) the  outstanding  principal  amount of the Loans,  (ii) the
aggregate  amount of Capitalized  Lease  Obligations and  Indebtedness for Money
Borrowed, and (iii) the aggregate amount of all Guarantees.

         "Unrestricted  Subsidiary" shall mean any Subsidiary of the Borrower or
any joint venture (which may represent a minority interest) between the Borrower
and/or any Subsidiary of the Borrower and any other Person,  in each case, which
the  Borrower  has   heretofore   designated  or  hereafter   designates  as  an
Unrestricted  Subsidiary by written notice to the  Administrative  Agent and the
Banks prior to the formation or acquisition of such Subsidiary or joint venture.
Notwithstanding the foregoing,  no Restricted Subsidiary may be re-designated as
an Unrestricted


                                      -19-


<PAGE>



Subsidiary  without the prior consent of the Majority  Banks.  The  Unrestricted
Subsidiaries  as of the  Agreement  Date are as set forth on Schedule 3 attached
hereto.

         "Unrestricted Subsidiary  Distributions" shall mean, (a) for any period
ending prior to June 30, 1997, the amount of any  distributions  received during
such  period  by  the  Borrower  and  its  Restricted   Subsidiaries   from  any
Unrestricted  Subsidiaries  (other  than in  connection  with the  repayment  of
intercompany  Indebtedness)  and (b) for all periods  after June 30,  1997,  the
lesser of (i) the amount of cash  distributions  received  during such period by
the Borrower and its Restricted  Subsidiaries  from any Unrestricted  Subsidiary
(other than in connection with the repayment of intercompany  Indebtedness)  and
(ii) fifteen percent (15%) of the sum of clauses (b)(i), (b)(ii) and (b)(iii) of
the definition of "Operating Cash Flow" set forth herein.

         "Use of  Proceeds  Letter"  shall  mean that  certain  Use of  Proceeds
Letter,  substantially in the form of Exhibit J attached hereto, to be delivered
to the Administrative Agent and the Banks on the date of any Advance hereunder.

         Each  definition  of an agreement in this Article 1 shall  include such
agreement as modified,  amended or supplemented  from time to time in accordance
herewith.


                                    ARTICLE 2

                                      Loans

         Section 2.1 The Loans. The Banks agree,  severally,  in accordance with
their respective  Commitment Ratios and not jointly,  upon the terms and subject
to the  conditions  of this  Agreement  and provided  there exists no Default or
Event of Default hereunder, to lend to the Borrower, prior to the Maturity Date,
an amount not at any one time  outstanding  to  exceed,  in the  aggregate,  the
Available  Commitment.  Subject to the terms and conditions  hereof and provided
there  exists no  Default  or Event of  Default  hereunder,  Advances  under the
Commitment may be repaid and reborrowed from time to time on a revolving basis.

         Section 2.2 Manner of Borrowing and Disbursement.

                  (a)  Choice of  Interest  Rate,  Etc.  Any  Advance  under the
Commitment shall, at the option of the Borrower,  be made as a Base Rate Advance
or a LIBOR  Advance;  provided,  however,  that at such time as there shall have
occurred and be continuing a Default hereunder,  the Borrower shall not have the
right to receive a LIBOR Advance.  Any notice given to the Administrative  Agent
in connection with a requested Advance hereunder shall be


                                      -20-


<PAGE>



given to the  Administrative  Agent prior to 11:00 a.m. (New York time) in order
for such  Business  Day to count  toward the  minimum  number of  Business  Days
required.

                  (b)      Base Rate Advances.

                         (i)   Advances.    The   Borrower    shall   give   the
         Administrative Agent in the case of Base Rate Advances at least one (1)
         Business Day's irrevocable prior telephonic notice followed immediately
         by a  Request  for  Advance;  provided,  however,  that the  Borrower's
         failure to confirm  any  telephonic  notice  with a Request for Advance
         shall  not  invalidate  any  notice  so  given  if  acted  upon  by the
         Administrative  Agent.  Upon receipt of such notice from the  Borrower,
         the  Administrative  Agent shall promptly notify each Bank by telephone
         or telecopy of the contents thereof.

                        (ii) Repayments and Reborrowings. The Borrower may repay
         or prepay a Base Rate  Advance  without  regard to its Payment Date and
         (A) upon at least one (1) Business Day's  irrevocable  prior telephonic
         notice  followed by written  notice,  reborrow  all or a portion of the
         principal  amount  thereof  as a Base Rate  Advance,  (B) upon at least
         three (3) Business Days'  irrevocable  prior telephonic notice followed
         by written notice,  reborrow all or a portion of the principal  thereof
         as one or more LIBOR  Advances,  or (C) not reborrow all or any portion
         of such Base Rate Advance. On the date indicated by the Borrower,  such
         Base Rate Advance  shall be so repaid and, as  applicable,  reborrowed.
         The failure to give timely notice hereunder with respect to the Payment
         Date of any Base Rate Advance  shall be considered a request for a Base
         Rate Advance.

                  (c)      LIBOR Advances.

                         (i) Advances.  Upon request, the Administrative  Agent,
         whose  determination  in absence of manifest error shall be conclusive,
         shall determine the available LIBOR Bases and shall notify the Borrower
         of such LIBOR Bases. The Borrower shall give the  Administrative  Agent
         in the case of  LIBOR  Advances  at  least  three  (3)  Business  Days'
         irrevocable prior telephonic  notice followed  immediately by a Request
         for Advance; provided,  however, that the Borrower's failure to confirm
         any  telephonic  notice with a Request for Advance shall not invalidate
         any notice so given if acted  upon by the  Administrative  Agent.  Upon
         receipt of such  notice from the  Borrower,  the  Administrative  Agent
         shall  promptly  notify  each  Bank by  telephone  or  telecopy  of the
         contents thereof.



                                      -21-


<PAGE>



                        (ii)  Repayments  and  Reborrowings.  At least three (3)
         Business  Days prior to the Payment  Date for each LIBOR  Advance,  the
         Borrower shall give the Administrative Agent telephonic notice followed
         by written  notice  specifying  whether  all or a portion of such LIBOR
         Advance (A) is to be repaid and then  reborrowed in whole or in part as
         one or more LIBOR Advances,  (B) is to be repaid and then reborrowed in
         whole or in part as a Base Rate Advance, or (C) is to be repaid and not
         reborrowed. The failure to give such notice shall preclude the Borrower
         from  reborrowing  such Advance as a LIBOR  Advance on its Payment Date
         and shall be  considered a request for a Base Rate  Advance.  Upon such
         Payment Date such LIBOR Advance will, subject to the provisions hereof,
         be so repaid and, as applicable, reborrowed.

                  (d)  Notification  of Banks.  Upon  receipt  of a Request  for
Advance,  or a notice from the Borrower with respect to any outstanding  Advance
prior to the  Payment  Date for such  Advance,  the  Administrative  Agent shall
promptly  but no later  than the  close of  business  on the day of such  notice
notify each Bank by telephone or telecopy of the contents thereof and the amount
of such Bank's  portion of the  Advance.  Each Bank shall,  not later than 12:00
noon (New York time) on the date of borrowing  specified  in such  notice,  make
available to the Administrative  Agent at the Administrative  Agent's Office, or
at such account as the Administrative  Agent shall designate,  the amount of its
portion of any Advance which  represents an  additional  borrowing  hereunder in
immediately available funds.

                  (e)      Disbursement.

                         (i) Prior to 2:00 p.m.  (New York  time) on the date of
         an Advance hereunder,  the Administrative  Agent shall,  subject to the
         satisfaction of the conditions set forth in Article 3 hereof,  disburse
         the amounts made available to the Administrative  Agent by the Banks in
         like funds by (A)  transferring  the amounts so made  available by wire
         transfer pursuant to the Borrower's instructions, or (B) in the absence
         of such  instructions,  crediting the amounts so made  available to the
         account of the Borrower maintained with the Administrative Agent.

                        (ii) Unless the Administrative Agent shall have received
         notice  from a Bank  prior to 12:00 noon (New York time) on the date of
         any   Advance   that  such  Bank  will  not  make   available   to  the
         Administrative  Agent such Bank's ratable portion of such Advance,  the
         Administrative  Agent may  assume  that such Bank has made or will make
         such portion available to the Administrative  Agent on the date of such
         Advance and the Administrative  Agent may in its sole discretion and in
         reliance upon such assumption, make


                                      -22-


<PAGE>



         available to the Borrower on such date a corresponding  amount.  If and
         to the extent the Bank does not make such ratable portion  available to
         the   Administrative   Agent,   such  Bank   agrees  to  repay  to  the
         Administrative  Agent on demand such corresponding amount together with
         interest  thereon,  for each day from  the  date  such  amount  is made
         available to the  Borrower  until the date such amount is repaid to the
         Administrative Agent, at the Federal Funds Rate.

                       (iii) If such  Bank  shall  repay  to the  Administrative
         Agent such corresponding amount, such amount so repaid shall constitute
         such Bank's  portion of the  applicable  Advance  for  purposes of this
         Agreement.  If such  Bank  does not  repay  such  corresponding  amount
         immediately  upon  the  Administrative  Agent's  demand  therefor,  the
         Administrative  Agent shall notify the Borrower and the Borrower  shall
         immediately pay such corresponding amount to the Administrative  Agent,
         with  interest  at the Federal  Funds Rate.  The failure of any Bank to
         fund its portion of any Advance shall not relieve any other Bank of its
         obligation,  if any,  hereunder to fund its  respective  portion of the
         Advance on the date of such borrowing, but no Bank shall be responsible
         for any such failure of any other Bank.

                        (iv) In the event that, at any time when the Borrower is
         not in Default and has otherwise  satisfied  each of the  conditions in
         Section 3.2 hereof,  a Bank for any reason fails or refuses to fund its
         portion of an Advance and such failure  shall  continue for a period in
         excess of thirty  (30)  days,  then,  until  such time as such Bank has
         funded its  portion  of such  Advance  (which  late  funding  shall not
         absolve such Bank from any liability it may have to the  Borrower),  or
         all  other  Banks  have  received  payment  in full  from the  Borrower
         (whether by repayment or  prepayment) or otherwise of the principal and
         interest due in respect of such Advance,  such  non-funding  Bank shall
         not have the right (A) to vote  regarding  any issue on which voting is
         required or advisable  under this Agreement or any other Loan Document,
         and  such  Bank's  portion  of  the  Loans  shall  not  be  counted  as
         outstanding for purposes of determining "Majority Banks" hereunder, and
         (B) to  receive  payments  of  principal,  interest  or fees  from  the
         Borrower, the Administrative Agent or the other Banks in respect of its
         portion of the Loans.



                                      -23-


<PAGE>



         Section 2.3 Interest.

                  (a) On Base Rate Advances.  Interest on each Base Rate Advance
shall be computed on the basis of a year of 365/366  days for the actual  number
of days elapsed and shall be payable at the Base Rate Basis for such Advance, in
arrears on the  applicable  Payment  Date.  Interest on Base Rate  Advances then
outstanding
shall also be due and payable on the Maturity Date.

                  (b) On LIBOR Advances. Interest on each LIBOR Advance shall be
computed on the basis of a 360-day  year for the actual  number of days  elapsed
and shall be  payable  at the LIBOR  Basis for such  Advance,  in arrears on the
applicable  Payment Date,  and, in addition,  if the Interest Period for a LIBOR
Advance  exceeds three (3) months,  interest on such LIBOR Advance shall also be
due and payable in arrears on every three-month  anniversary of the beginning of
such Interest Period.  Interest on LIBOR Advances then outstanding shall also be
due and payable on the Maturity Date.

                  (c) Interest if no Notice of Selection of Interest Rate Basis.
If the Borrower  fails to give the  Administrative  Agent  timely  notice of its
selection  of a LIBOR  Basis,  or if for any reason a  determination  of a LIBOR
Basis for any Advance is not timely  concluded,  the Base Rate Basis shall apply
to such Advance.

                  (d) Interest Upon Default.  Immediately upon the occurrence of
an Event of Default  hereunder,  the outstanding  principal balance of the Loans
shall bear  interest  at the Default  Rate.  Such  interest  shall be payable on
demand by the Majority Banks and shall accrue until the earlier of (i) waiver or
cure of the  applicable  Event of Default,  (ii) agreement by the Majority Banks
(or, if applicable to the underlying Event of Default, the Banks) to rescind the
charging  of  interest  at the  Default  Rate,  or (iii)  payment in full of the
Obligations.

                  (e)      LIBOR Contracts.  At no time may the number of
outstanding LIBOR Advances exceed six (6).

                  (f)      Applicable Margin.  With respect to any Advance,
the Applicable Margin shall be as set forth in a certificate of
the chief financial officer of the Borrower delivered to the
Administrative Agent based upon the Applicable Margin Ratio for
the most recent fiscal quarter end for which financial statements


                                      -24-


<PAGE>



are furnished by the Borrower to the Administrative  Agent and each Bank for the
fiscal quarter most recently ended as follows:


        Applicable Margin Ratio       Base Rate Advance        LIBOR Advance
                                      Applicable Margin      Applicable Margin

A.      Greater than or equal              1.250%                 2.500%
        to 5.50:1

B.      Greater than or equal              1.125%                 2.375%
        to 5.00:1, but less
        than 5.50:1

C.      Greater than or equal              0.875%                 2.125%
        to 4.50:1, but less
        than 5.00:1

D.      Greater than or equal              0.625%                 1.875%
        to 4.00:1, but less
        than 4.50:1

E.      Less than 4.00:1                   0.250%                 1.500%


Changes to the  Applicable  Margin  shall be  effective  (i) with  respect to an
increase in the Applicable Margin, as of the second (2nd) Business Day after the
day on which the  financial  statements  are  required  to be  delivered  to the
Administrative  Agent and the Banks  pursuant  to  Section  6.1 or  Section  6.2
hereof, as the case may be; provided,  however, if such financial statements are
not  delivered to the  Administrative  Agent and the Banks on or before the date
specified  in such  Section,  such  increase  shall be  effective as of the date
specified  in such Section for delivery of the  financial  statements,  and (ii)
with respect to a decrease in the Applicable  Margin, as of the later of (A) the
second (2nd) Business Day after the day on which such  financial  statements are
required to be delivered  pursuant to Section 6.1 or Section 6.2 hereof,  as the
case may be, and (B) the date on which such  financial  statements  are actually
delivered to the Administrative Agent and the Banks.

         Upon the occurrence and during the  continuance of an Event of Default,
the  Applicable  Margins shall not be subject to downward  adjustment  and shall
automatically  revert to the Applicable Margins set forth in part A of the above
table until such time as such Event of Default is cured or waived.

         Section 2.4                Commitment Fees.

         (a) Commencing on the Agreement Date, and continuing  until the date of
the first Advance  hereunder,  the Borrower agrees to pay to the  Administrative
Agent for the account of each of the Banks,  in accordance  with its  respective
Commitment Ratio, a


                                      -25-


<PAGE>



commitment  fee on the amount of the  Commitment for each day from the Agreement
Date until the date of the first Advance  hereunder of a rate of  one-quarter of
one percent  (0.250%)  per annum,  which fee shall be computed on the basis of a
year of 365/366 days for the actual number of days elapsed,  shall be payable on
the date of the first Advance hereunder,  and shall be fully earned when due and
non-refundable when paid.

          (b)  Commencing on the date of the first Advance  hereunder and of all
times thereafter, the Borrower agrees to pay to the Administrative Agent for the
account of each of the Banks in accordance with its respective Commitment Ratio,
a commitment fee on the aggregate  unborrowed balance of the Commitment for each
day from the date of the first Advance  hereunder  until the Maturity Date, at a
rate of (i)  one-half  of one  percent  (0.500%)  per annum when the  Applicable
Margin Ratio is greater than or equal to 4.00:1;  and (ii)  three-eighths of one
percent (0.375%) per annum when the Applicable Margin Ratio is less than 4.00:1.
Such commitment fee shall be computed on the basis of a year of 365/366 days for
the actual number of days elapsed,  shall be payable quarterly in arrears on the
last Business Day of each calendar quarter,  and shall be fully earned when due,
and shall be  non-refundable  when paid. A final payment of any  commitment  fee
then payable shall also be due and payable on the Maturity Date.

         Section 2.5                Mandatory Commitment Reductions.

                  (a) Scheduled Reductions. Commencing on September 30, 1999 and
at the end of each calendar quarter  thereafter,  the Commitment as of September
29,  1999 shall be  automatically  and  permanently  reduced as set forth  below
(which reductions are in addition to those set forth in Sections 2.5(b), 2.5(c),
2.5(d) and 2.6 hereof):


                                                   Quarterly Percentage
                                                      of Reduction of
    Dates of Commitment Reduction                      Commitment as
                                                   of September 29, 1999

September 30, 1999 and December 31, 1999                  3.750%

March 31, 2000, June 30, 2000,                            3.125%
September 30, 2000 and December 31, 2000

March 31, 2001, June 30, 2001,                            4.375%
September 30, 2001 and December 31, 2001

March 31, 2002, June 30, 2002,                            5.625%
September 30, 2002 and December 31, 2002



                                      -26-


<PAGE>





March 31, 2003, June 30, 2003,                            5.625%
September 30, 2003 and December 31, 2003

March 31, 2004, June 30, 2004                             4.375%
September 30, 2004 and Maturity Date



The Borrower  shall make a repayment  of the Loans  outstanding,  together  with
accrued interest  thereon,  on or before the effective date of each reduction in
the  Commitment  under this Section  2.5(a),  such that the aggregate  principal
amount of the Loans outstanding at no time exceeds the Commitment as so reduced.
Any remaining  unpaid  principal and interest under the Commitment  shall be due
and payable in full on the Maturity  Date, and the  Commitment  shall  thereupon
terminate.

                  (b) Reduction From Excess Cash Flow. On April 15, 2000, and on
each April 15 thereafter during the term of this Agreement, the Commitment shall
be permanently  reduced by an amount equal to fifty percent (50%) of Excess Cash
Flow for the fiscal year immediately  preceding the calculation date. Reductions
to the  Commitment  under this Section  shall be applied to the  reductions  set
forth in Section  2.5(a)  hereof in inverse  order of the  reductions  set forth
therein.

                  (c) Reduction From Permitted  Asset Sales. On the Business Day
following  the  date  of  receipt  by the  Borrower  or  any  of its  Restricted
Subsidiaries of the Net Proceeds of any asset sale permitted pursuant to Section
7.4 hereof  (other  than with  respect  to the  Philadelphia  Disposition),  the
Commitment shall be automatically and permanently  reduced by an amount equal to
such Net Proceeds;  provided, however, that the Commitment shall not be required
to be  reduced  by such Net  Proceeds  until the  amount of such  unapplied  Net
Proceeds exceeds $250,000 in the aggregate; provided, further, however, that the
Borrower may notify the  Administrative  Agent in writing that it intends to use
any or all of such Net Proceeds to acquire fixed or capital assets  permitted by
Section  7.6  hereof  within  six (6)  months of the date of receipt of such Net
Proceeds, in which case, the reduction in the Commitment up to the amount of the
Net  Proceeds  intended to be used which is  otherwise  required by this Section
2.5(c) need not be made, but if all or part of such Net Proceeds are not used or
irrevocably  committed to be used within such  6-month  period,  the  Commitment
shall be  permanently  reduced by an amount  equal to such Net  Proceeds  on the
earlier of (i) the first day following  the end of such 6-month  period and (ii)
the date on which the


                                      -27-


<PAGE>



Borrower has reasonably  determined that such Net Proceeds shall not be so used.
Reductions  to the  Commitment  under  this  Section  shall  be  applied  to the
reductions set forth in Section 2.5(a) hereof in inverse order of the reductions
set forth therein.

                  (d) Reduction From Sale of Capital Stock and Debt Instruments.
On the  Business  Day  following  the date of receipt by the Borrower of the net
proceeds of any sale its Capital Stock or debt  instruments or other  securities
(other than an amount not to exceed $2,000,000 in the aggregate from the sale of
securities in connection  with any employee  stock option plan of the Borrower),
the Commitment shall automatically and permanently be reduced by an amount equal
(i) 100% of such net proceeds to the extent the  Leverage  Ratio is greater than
or equal to 4.0:1;  or (ii) 50% of such net  proceeds to the extent the Leverage
Ratio is less than 4.0:1;  provided,  however,  the  provisions  of this Section
2.5(d) shall not apply to equity  contributions  by the Parent or American Radio
Systems. Reductions to the Commitment under this Section shall be applied to the
reductions set forth in Section 2.5(a) hereof in inverse order of the reductions
set forth therein.

         Section 2.6 Voluntary  Commitment  Reductions.  The Borrower shall have
the right,  at any time and from time to time after the Agreement Date and prior
to the  Maturity  Date,  upon at least three (3)  Business  Days' prior  written
notice to the  Administrative  Agent,  without premium or penalty,  to cancel or
reduce permanently all or a portion of the Commitment, on a pro rata basis among
the Banks,  provided,  however, that any such -------- ------- partial reduction
shall be made in an amount not less than $5,000,000 and in integral multiples of
not less than $1,000,000.  As of the date of cancellation or reduction set forth
in such notice, the Commitment shall be permanently reduced to the amount stated
in the Borrower's notice for all purposes herein,  and the Borrower shall pay to
the  Administrative  Agent for the  Banks the  amount  necessary  to reduce  the
principal amount of the Loans then outstanding  under the Commitment to not more
than the amount of the Commitment as so reduced,  together with accrued interest
on the amount so prepaid and  commitment  fees  accrued  through the date of the
reduction  with  respect to the amount  reduced.  Reductions  in the  Commitment
pursuant  to this  Section  shall be  applied  pro  rata to the  then  remaining
reductions set forth in Section 2.5(a).



                                      -28-


<PAGE>



         Section 2.7 Prepayments and Repayments.

                  (a) Prepayment.  The principal amount of any Base Rate Advance
may be  prepaid  in full or ratably  in part at any time,  without  penalty  and
without  regard to the Payment  Date for such  Advance.  LIBOR  Advances  may be
prepaid  prior to the  applicable  Payment Date,  upon three (3) Business  Days'
prior written  notice to the  Administrative  Agent,  provided that the Borrower
shall  reimburse  the  Banks  and the  Administrative  Agent,  on  demand by the
applicable  Bank  or the  Administrative  Agent,  for  any  loss  or  reasonable
out-of-pocket  expense  incurred  by any  Bank or the  Administrative  Agent  in
connection  with such  prepayment,  as set forth in  Section  2.10  hereof.  Any
prepayment  hereunder  shall be in  amounts  of not less  than  $500,000  and in
integral multiples of $100,000.

                  (b)      Repayments.

                         (i) Loans in Excess of Commitment. If, at any time, the
         amount  of the  Loans  then  outstanding  shall  exceed  the  Available
         Commitment,  the Borrower  shall,  on such date and subject to Sections
         2.10 and 2.11 hereof,  make a repayment of the principal  amount of the
         Loans in an amount  equal to such  excess,  together  with any  accrued
         interest and fees with respect thereto.

                        (ii) From Excess Cash Flow.  On April 15,  2000,  and on
         each  April  15  thereafter  during  the  term of this  Agreement,  the
         Borrower  shall make a repayment  of the Loans then  outstanding  in an
         amount  equal to fifty  percent  (50%) of the Excess  Cash Flow for the
         fiscal year immediately preceding the calculation date.


                       (iii) From  Permitted  Asset  Sales.  On the Business Day
         following the date of receipt by the Borrower or any of its  Restricted
         Subsidiaries  of the Net Proceeds of any asset sale permitted  pursuant
         to Section  7.4 hereof  (other  than with  respect to the  Philadelphia
         Disposition), and to the extent that the Borrower is required to reduce
         the Commitment  pursuant to Section  2.5(c) hereof,  the Borrower shall
         make a repayment  of the Loans by an amount equal to the amount of such
         reduction.

                        (iv) From  Capital  Stock and Debt  Instruments.  On the
         Business Day  following the receipt by the Borrower of the Net Proceeds
         of any  sale  of  its  Capital  Stock  or  debt  instruments  or  other
         securities,  and to the extent that the  Borrower is required to reduce
         the Commitment  pursuant to Section  2.5(d) hereof,  the Borrower shall
         make a repayment


                                      -29-


<PAGE>



         of the Loans by an amount equal to the amount of such
         reduction.

                         (v) Maturity Date.  In addition  to  the  foregoing,  a
         final payment of all Obligations then  outstanding  shall  be  due  and
         payable on the Maturity Date.

         Section 2.8 Notes; Loan Accounts.

                  (a) The Loans shall be repayable in accordance  with the terms
and  provisions  set forth herein and shall be evidenced by the Notes.  One Note
shall be payable  to the order of each  Bank,  in  accordance  with such  Bank's
respective  Commitment  Ratio.  The Notes shall be issued by the Borrower to the
Banks  and  shall  be duly  executed  and  delivered  by one or more  Authorized
Signatories.

                  (b) Each Bank may open and  maintain  on its books in the name
of the  Borrower a loan  account  with  respect to its  portion of the Loans and
interest  thereon.  Each Bank which opens such a loan  account  shall debit such
loan account for the principal  amount of its portion of each Advance made by it
and  accrued  interest  thereon,  and shall  credit  such loan  account for each
payment on account of  principal  of or interest on its Loans.  The records of a
Bank with  respect to the loan  account  maintained  by it shall be prima  facie
evidence  of its  portion  of the  Loans and  accrued  interest  thereon  absent
manifest  error,  but the failure of any Bank to make any such  notations or any
error or mistake in such  notations  shall not affect the  Borrower's  repayment
obligations with respect to such Loans.

         Section 2.9 Manner of Payment.

                  (a) Each payment (including any prepayment) by the Borrower on
account of the  principal of or interest on the Loans,  commitment  fees and any
other amount owed to the Banks or the Administrative  Agent or any of them under
this  Agreement  or the Notes  shall be made not later than 1:00 p.m.  (New York
time)  on  the  date   specified  for  payment  under  this   Agreement  to  the
Administrative  Agent at the  Administrative  Agent's Office, for the account of
the Banks or the  Administrative  Agent,  as the case may be, in lawful money of
the  United  States of America  in  immediately  available  funds.  Any  payment
received by the  Administrative  Agent after 1:00 p.m.  (New York time) shall be
deemed received on the next Business Day. Receipt by the Administrative Agent of
any payment  intended for any Bank or Banks  hereunder  prior to 1:00 p.m.  (New
York time) on any  Business  Day shall be deemed to  constitute  receipt by such
Bank or Banks on such  Business Day. In the case of a payment for the account of
a Bank, the Administrative  Agent will promptly,  but no later than the close of
business on the date such payment is


                                      -30-


<PAGE>



deemed received,  thereafter  distribute the amount so received in like funds to
such Bank. If the Administrative  Agent shall not have received any payment from
the Borrower as and when due, the Administrative  Agent will promptly notify the
Banks accordingly. In the event that the Administrative Agent shall fail to make
distribution to any Bank as required under this Section 2.9, the  Administrative
Agent agrees to pay such Bank  interest from the date such payment was due until
paid at the Federal Funds Rate.

                  (b) The Borrower agrees to pay principal,  interest,  fees and
all  other  amounts  due  hereunder  or  under  the  Notes  without  set-off  or
counterclaim or any deduction whatsoever.

                  (c)  Prior to the  declaration  of an Event of  Default  under
Section 8.2 hereof,  if some but less than all amounts due from the Borrower are
received  by the  Administrative  Agent  with  respect to the  Obligations,  the
Administrative  Agent shall  distribute  such amounts in the following  order of
priority, all on a pro rata basis to the Banks: (i) to the payment on a pro rata
basis of any fees or expenses then due and payable to the  Administrative  Agent
or the  Banks,  or any of them;  (ii) to the  payment of  interest  then due and
payable on the Loans;  (iii) to the payment of all other  amounts not  otherwise
referred to in this  Section  2.9(c) then due and payable to the  Administrative
Agent or the Banks,  or any of them,  hereunder  or under the Notes or any other
Loan Document;  and (iv) to the payment of principal then due and payable on the
Loans.

                  (d) Subject to any contrary  provisions  in the  definition of
Interest  Period,  if any payment under this  Agreement or any of the other Loan
Documents is specified to be made on a day which is not a Business Day, it shall
be made on the next Business Day, and such  extension of time shall in such case
be included in computing  interest  and fees,  if any, in  connection  with such
payment.

         Section 2.10 Reimbursement.

                  (a)  Whenever  any Bank  shall  sustain or incur any losses or
reasonable out-of-pocket expenses in connection with (i) failure by the Borrower
to borrow any LIBOR Advance after having given notice of its intention to borrow
in  accordance  with  Section 2.2 hereof  (whether  by reason of the  Borrower's
election  not to proceed or the  non-fulfillment  of any of the  conditions  set
forth in Article  3), or (ii)  prepayment  (or  failure to prepay  after  giving
notice  thereof) of any LIBOR  Advance in whole or in part for any  reason,  the
Borrower  agrees  to pay to such  Bank,  upon  such  Bank's  demand,  an  amount
sufficient  to  compensate  such  Bank for all  such  losses  and  out-of-pocket
expenses.  Such Bank's good faith  determination of the amount of such losses or
out-of-pocket expenses, as set forth in writing and accompanied


                                      -31-


<PAGE>



by calculations  in reasonable  detail  demonstrating  the basis for its demand,
shall be presumptively correct absent manifest error.

                  (b) Losses subject to  reimbursement  hereunder shall include,
without  limiting  the  generality  of the  foregoing,  lost  margins,  expenses
incurred by any Bank or any  participant  of such Bank  permitted  hereunder  in
connection with the re-employment of funds prepaid,  paid, repaid, not borrowed,
or not paid,  as the case may be, and will be payable  whether the Maturity Date
is changed by virtue of an amendment  hereto  (unless such  amendment  expressly
waives such payment) or as a result of acceleration of the Obligations.

         Section 2.11 Pro Rata Treatment.

                  (a) Advances. Each Advance from the Banks hereunder,  shall be
made pro rata on the basis of the respective Commitment Ratios of the Banks.

                  (b) Payments.  Each payment and prepayment of principal of the
Loans,  and,  except as provided in Section  2.2(e) and Article 10 hereof,  each
payment of  interest  on the  Loans,  shall be made to the Banks pro rata on the
basis of their respective unpaid principal  amounts  outstanding under the Notes
immediately  prior to such payment or  prepayment.  If any Bank shall obtain any
payment (whether  involuntary,  through the exercise of any right of set-off, or
otherwise)  on account of the Loans in excess of its ratable  share of the Loans
under its Commitment  Ratio,  such Bank shall forthwith  purchase from the other
Banks such  participations  in the portion of the Loans made by them as shall be
necessary to cause such purchasing Bank to share the excess payment ratably with
each of them;  provided,  however,  that if all or any  portion  of such  excess
payment is thereafter  recovered from such  purchasing  Bank, such purchase from
each Bank shall be rescinded  and such Bank shall repay to the  purchasing  Bank
the purchase price to the extent of such recovery.  The Borrower agrees that any
Bank so  purchasing a  participation  from another Bank pursuant to this Section
2.11(b) may, to the fullest extent permitted by law,  exercise all its rights of
payment  (including the right of set-off) with respect to such  participation as
fully as if such Bank were the direct  creditor of the Borrower in the amount of
such participation.

         Section 2.12 Capital Adequacy.  If after the date hereof,  the adoption
of any  Applicable  Law regarding the capital  adequacy of banks or bank holding
companies,  or any change in Applicable Law (whether adopted before or after the
Agreement Date) or any change in the interpretation or administration thereof by
any governmental  authority,  central bank or comparable agency charged with the
interpretation  or administration  thereof,  or compliance by such Bank with any
directive regarding capital adequacy


                                      -32-


<PAGE>



(whether  or not  having the force of law) of any such  governmental  authority,
central bank or comparable  agency, has or would have the effect of reducing the
rate of  return  on any  Bank's  capital  as a  consequence  of its  obligations
hereunder  with  respect to the Loans and the  Commitment  to a level below that
which it could have achieved but for such adoption, change or compliance (taking
into  consideration  such  Bank's  policies  with  respect to  capital  adequacy
immediately  before such  adoption,  change or compliance and assuming that such
Bank's capital was fully utilized prior to such adoption,  change or compliance)
by an amount reasonably deemed by such Bank to be material, then, upon demand by
such Bank, the Borrower shall promptly pay to such Bank such additional  amounts
as shall be sufficient to compensate such Bank for such reduced return, together
with  interest on such amount from the fourth (4th)  Business Day after the date
of demand or the Maturity Date, as applicable,  until payment in full thereof at
the Default Rate. A certificate of such Bank setting forth the amount to be paid
to such  Bank by the  Borrower  as a result  of any  event  referred  to in this
paragraph  and   supporting   calculations   in   reasonable   detail  shall  be
presumptively correct absent manifest error.

         Section 2.13 Bank Tax Forms.  On or prior to the Agreement  Date and on
or prior to the first Business Day of each calendar year  thereafter,  each Bank
which is organized in a jurisdiction  other than the United States shall provide
each of the  Administrative  Agent and the  Borrower  with a  properly  executed
originals  of  Forms  4224 or 1001 (or any  successor  form)  prescribed  by the
Internal Revenue Service or other documents satisfactory to the Borrower and the
Administrative  Agent, and properly  executed Internal Revenue Service Forms W-8
or W-9, as the case may be, certifying (i) as to such Bank's status for purposes
of determining  exemption from United States  withholding  taxes with respect to
all payments to be made to such Bank  hereunder and under the Notes or (ii) that
all payments to be made to such Bank  hereunder  and under the Notes are subject
to such taxes at a rate reduced to zero by an applicable  tax treaty.  Each such
Bank agrees to provide the Administrative  Agent and the Borrower with new forms
prescribed by the Internal  Revenue  Service upon the expiration or obsolescence
of any previously delivered form, or after the occurrence of any event requiring
a change in the most recent forms  delivered by it to the  Administrative  Agent
and the Borrower.




                                      -33-


<PAGE>



                                    ARTICLE 3

                              Conditions Precedent

         Section 3.1 Conditions  Precedent to Initial Advance. The obligation of
the Banks to undertake the Commitment and to make the initial Advance  hereunder
are subject to the prior or contemporaneous fulfillment of each of the following
conditions:

                  (a)      The Administrative Agent and the Banks shall have
received each of the following:

                         (i)        this Agreement duly executed;

                        (ii) the loan  certificate  of the Borrower  dated as of
         the  Agreement  Date,  in  substantially  the form  attached  hereto as
         Exhibit K, including a certificate  of incumbency  with respect to each
         Authorized Signatory of such Person, together with the following items:
         (A)  a  true,   complete  and  correct  copy  of  the   Certificate  of
         Incorporation and By-laws of the Borrower as in effect on the Agreement
         Date, (B)  certificates of good standing for the Borrower issued by the
         Secretary  of  State  or  similar  state  official  for  the  state  of
         incorporation  of the Borrower and for each state in which the Borrower
         is required to qualify to do business, (C) a true, complete and correct
         copy of the  corporate  resolutions  of the  Borrower  authorizing  the
         Borrower to execute,  deliver and perform this  Agreement and the other
         Loan  Documents,  and  (D) a true,  complete  and  correct  copy of any
         shareholders'  agreements  or voting  trust  agreements  in effect with
         respect to the stock of the Borrower;

                       (iii)        duly executed Notes;

                        (iv)        duly executed Security Documents;

                         (v)  copies  of  insurance   binders  or   certificates
         covering the assets of the Borrower  and its  Restricted  Subsidiaries,
         and otherwise meeting the requirements of Section 5.5 hereof,  together
         with copies of the underlying insurance policies;

                        (vi) legal  opinion of Sullivan & Worcester  LLP counsel
         to the Borrower;  addressed to each Bank and the  Administrative  Agent
         and dated as of the Agreement Date;

                       (vii) duly executed  Certificate  of Financial  Condition
         for the Borrower and its Restricted  Subsidiaries on a consolidated and
         consolidating  basis,  given  by the  chief  financial  officer  of the
         Borrower;



                                      -34-


<PAGE>



                      (viii)  copies  of the  most  recent  quarterly  financial
         statements of the Borrower and its Restricted  Subsidiaries provided to
         each  Bank  and  each  Administrative  Agent,  certified  by the  chief
         financial officer of the Borrower;

                        (ix)  all such  other  documents  as the  Administrative
         Agent may reasonably request,  certified by an appropriate governmental
         official or an Authorized Signatory if so requested.

                  (b) The Administrative Agent and the Banks shall have received
evidence satisfactory to them that all Necessary  Authorizations,  including all
necessary consents to the closing of this Agreement, have been obtained or made,
are in full  force and  effect and are not  subject  to any  pending  or, to the
knowledge  of  the  Borrower,  threatened  reversal  or  cancellation,  and  the
Administrative  Agent and the Banks  shall  have  received a  certificate  of an
Authorized Signatory so stating.

                  (c) The Borrower shall certify to the Administrative Agent and
the Banks that each of the  representations  and  warranties in Article 4 hereof
are true and correct in all material  respects as of the Agreement Date and that
no Default or Event of Default then exists or is continuing.

                  (d) The  Administrative  Agent  shall have  received  evidence
reasonably  satisfactory  to it that the Parent or  American  Radio  Systems has
contributed not less than  $25,000,000 of equity into the Borrower  comprised of
not less  than  $15,000,000  in cash (or  acquisitions  of  property  from  non-
Affiliates made with Capital Stock of American Radio Systems) and the balance in
tangible assets (valued at American Radio Systems's cost for such assets).

                  (e) The Borrower shall have paid to the  Administrative  Agent
for the  account  of each  Bank  the  facility  fees set  forth in those  letter
agreements dated the Agreement Date in favor of each Bank.

                  (f) The  Administrative  Agent  shall have  received  evidence
reasonably  satisfactory  to it that no real  property  owned by the Borrower is
located in a Federal or state  designated  flood zone or, to the extent that any
such real  property  is  located in a Federal or state  designated  flood  zone,
evidence  satisfactory  to it that such real  property is  sufficiently  insured
against flood related losses.

         Section 3.2 Conditions Precedent to Each Advance. The obligation of the
Banks to make each  Advance  on or after the  Agreement  Date is  subject to the
fulfillment of each of the


                                      -35-


<PAGE>



following conditions immediately prior to or contemporaneously
with such Advance:

                  (a) All of the  representations and warranties of the Borrower
under  this  Agreement  and  the  other  Loan  Documents   (including,   without
limitation,  all  representations  and warranties with respect to the Borrower's
Restricted Subsidiaries), which, pursuant to Section 4.2 hereof, are made at and
as of the time of such  Advance,  shall be true and  correct at such time in all
material respects, both before and after giving effect to the application of the
proceeds of such Advance,  and after giving effect to any updates to information
provided to the Banks in accordance with the terms of such  representations  and
warranties, and no Default hereunder shall then exist or be caused thereby;

                  (b) With respect to Advances which, if funded,  would increase
the   aggregate   principal   amount  of  Loans   outstanding   hereunder,   the
Administrative Agent shall have received a duly executed Request for Advance;

                  (c) The Administrative Agent and the Banks shall have received
all such other certificates,  reports, statements,  opinions of counsel (if such
Advance  is in  connection  with  an  Acquisition)  or  other  documents  as the
Administrative Agent or any Bank may reasonably request;

                  (d) With respect to any Advance relating to any Acquisition or
the formation of any Subsidiary which is permitted hereunder, the Administrative
Agent and the Banks shall have received such documents and instruments  relating
to such Acquisition or formation of a new Restricted Subsidiary as are described
in Section 5.14 hereof or otherwise required herein.



                                    ARTICLE 4

                         Representations and Warranties

         Section 4.1 Representations and Warranties. The Borrower hereby agrees,
represents and warrants, upon the Agreement Date, in favor of the Administrative
Agent and each Bank that:

                  (a)  Organization;   Ownership;  Power;   Qualification.   The
Borrower is a corporation duly organized,  validly existing and in good standing
under the laws of the State of Delaware.  The Borrower has the  corporate  power
and  authority to own its  properties  and to carry on its business as now being
and as  proposed  hereafter  to be  conducted.  Except as set forth on  Schedule
4.1(a) attached hereto, each Restricted Subsidiary of


                                      -36-


<PAGE>



the  Borrower is a  corporation  duly  organized,  validly  existing and in good
standing under the laws of the state of its  incorporation and has the corporate
power and  authority to own its  properties  and to carry on its business as now
being and as proposed  hereafter to be  conducted.  The Borrower and each of its
Restricted  Subsidiaries are duly qualified,  in good standing and authorized to
do business in each  jurisdiction  in which the  character  of their  respective
properties  or  the  nature  of  their  respective   businesses   requires  such
qualification or authorization,  except where failure to be so qualified, in the
aggregate, could not reasonably be expected to have a Material Adverse Effect.

                  (b)  Authorization;   Enforceability.  The  Borrower  has  the
corporate power and has taken all necessary  corporate action to authorize it to
borrow hereunder, to execute, deliver and perform this Agreement and each of the
other Loan Documents to which it is a party in accordance with their  respective
terms, and to consummate the transactions  contemplated hereby and thereby. This
Agreement  has been duly executed and delivered by the Borrower and is, and each
of the other Loan  Documents to which the  Borrower is party is, a legal,  valid
and binding  obligation  of the  Borrower  enforceable  against the  Borrower in
accordance with its terms, subject, as to enforcement of remedies, to applicable
bankruptcy,  insolvency, fraudulent conveyance,  reorganization,  moratorium and
similar laws affecting creditors' rights and remedies generally, and subject, as
to enforceability, to general principles of equity.

                  (c)   Subsidiaries:    Authorization;    Enforceability.   The
Borrower's  Restricted  Subsidiaries  and the  Borrower's  direct  and  indirect
ownership  thereof as of the Agreement Date are as set forth on Schedule  4.1(c)
attached   hereto,   and  to  the  extent  such  Restricted   Subsidiaries   are
corporations,  the  Borrower has the  unrestricted  right to vote the issued and
outstanding shares of the Restricted  Subsidiaries shown thereon and such shares
of such  Restricted  Subsidiaries  have been duly  authorized and issued and are
fully paid and nonassessable. Each Restricted Subsidiary of the Borrower has the
corporate power and has taken all necessary  corporate action to authorize it to
execute,  deliver and perform each of the Loan  Documents to which it is a party
in accordance  with their  respective  terms and to consummate the  transactions
contemplated  by this  Agreement  and by such Loan  Documents.  Each of the Loan
Documents  to which any  Restricted  Subsidiary  of the  Borrower  is party is a
legal,  valid and binding obligation of such Restricted  Subsidiary  enforceable
against such  Restricted  Subsidiary in accordance with its terms,  subject,  as
enforcement  of  remedies,  to  applicable  bankruptcy,  insolvency,  fraudulent
conveyance,  reorganization,  moratorium and similar laws  affecting  creditors'
rights and remedies  generally,  and subject,  as to enforceability,  to general
principles of equity. The Borrower's


                                      -37-


<PAGE>



ownership interest in each of its Restricted Subsidiaries represents a direct or
indirect  controlling  interest of such  Restricted  Subsidiary  for purposes of
directing  or causing  the  direction  of the  management  and  policies of each
Restricted Subsidiary.

                  (d)  Compliance  with Other Loan  Documents  and  Contemplated
Transactions.  The execution, delivery and performance, in accordance with their
respective  terms,  by the Borrower of this Agreement and the Notes,  and by the
Borrower and its Restricted  Subsidiaries of each of the other Loan Documents to
which they are  respectively  party,  and the  consummation of the  transactions
contemplated  hereby and thereby, do not and will not (i) require any consent or
approval,  governmental  or otherwise,  not already  obtained,  (ii) violate any
Applicable  Law  respecting  the Borrower or any  Restricted  Subsidiary  of the
Borrower,  (iii) conflict  with,  result in a breach of, or constitute a default
under the  certificate  or articles of  incorporation  or by-laws or partnership
agreements, as the case may be, as amended, of the Borrower or of any Restricted
Subsidiary of the Borrower, or under any material indenture, agreement, or other
instrument,  including without limitation the Licenses, to which the Borrower or
any of its Restricted  Subsidiaries  is a party or by which any of them or their
respective properties may be bound, or (iv) result in or require the creation or
imposition  of any  Lien  upon or with  respect  to any  property  now  owned or
hereafter acquired by the Borrower or any of its Restricted Subsidiaries, except
for Permitted Liens.

                  (e) Business. The Borrower, together with its Subsidiaries, is
engaged  in the  business  of owning,  constructing,  managing,  operating,  and
investing in communications tower facilities.

                  (f) Licenses,  etc. The Licenses have been duly issued and are
in full force and effect.  The Borrower and its Restricted  Subsidiaries  are in
compliance in all material  respects  with all of the  provisions  thereof.  The
Borrower  and  its   Restricted   Subsidiaries   have   secured  all   Necessary
Authorizations  and all such  Necessary  Authorizations  are in full  force  and
effect.  Neither any License nor any Necessary  Authorization  is the subject of
any pending or, to the best of the Borrower's knowledge, threatened revocation.

                  (g)  Compliance  with Law.  The  Borrower  and its  Restricted
Subsidiaries are in compliance with all Applicable Law, except where the failure
to be in compliance  would not  individually or in the aggregate have a Material
Adverse Effect.

                  (h) Title to Assets.  As of the Agreement  Date,  the Borrower
and its Restricted Subsidiaries have good, legal and


                                      -38-


<PAGE>



marketable title to, or a valid leasehold  interest in, all of its assets.  None
of  the  properties  or  assets  of  the  Borrower  or  any  of  its  Restricted
Subsidiaries  is subject to any Liens,  except for Permitted  Liens.  Except for
financing  statements  evidencing  Permitted Liens, no financing statement under
the Uniform Commercial Code as in effect in any jurisdiction and no other filing
which names the  Borrower  or any of its  Restricted  Subsidiaries  as debtor or
which  covers or purports  to cover any of the assets of the  Borrower or any of
its Restricted  Subsidiaries is currently  effective and on file in any state or
other  jurisdiction,  and  neither  the  Borrower  nor  any  of  its  Restricted
Subsidiaries  has signed any such financing  statement or filing or any security
agreement  authorizing  any secured party  thereunder to file any such financing
statement or filing.

                  (i)  Litigation.  As of the date  hereof,  there is no action,
suit,  proceeding or investigation  pending against, or, to the knowledge of the
Borrower,  threatened  against or in any other manner relating adversely to, the
Borrower  or any of  its  Restricted  Subsidiaries  or any of  their  respective
properties,  including without  limitation the Licenses,  in any court or before
any  arbitrator  of any kind or before or by any  governmental  body  (including
without  limitation  the FCC)  except as set forth on Schedule  4.1(i)  attached
hereto (as such  schedule  may be updated  from time to time).  No such  action,
suit,  proceeding or investigation  (i) calls into question the validity of this
Agreement  or any other Loan  Document,  or (ii)  individually  or  collectively
involves  the  possibility  of any judgment or  liability  not fully  covered by
insurance  which,  if  determined  adversely  to  the  Borrower  or  any  of its
Restricted Subsidiaries, would have a Materially Adverse Effect.

                  (j) Taxes.  All  federal,  state and other tax  returns of the
Borrower  and each of its  Restricted  Subsidiaries  required by law to be filed
have been duly filed and all federal, state and other taxes, including,  without
limitation,  withholding taxes,  assessments and other  governmental  charges or
levies required to be paid by the Borrower or any of its Restricted Subsidiaries
or imposed upon the  Borrower or any of its  Restricted  Subsidiaries  or any of
their  respective  properties,  income,  profits  or  assets,  which are due and
payable,  have been paid, except any such taxes (i) (x) the payment of which the
Borrower or any of its Restricted  Subsidiaries is diligently contesting in good
faith by  appropriate  proceedings,  (y) for which  adequate  reserves have been
provided  on the  books of the  Borrower  or the  Restricted  Subsidiary  of the
Borrower  involved,  and (z) as to which no Lien other than a Permitted Lien has
attached and no foreclosure,  distraint,  sale or similar  proceedings have been
commenced, or (ii) which may result from audits not yet conducted.  The charges,
accruals and  reserves on the books of the  Borrower and each of its  Restricted
Subsidiaries


                                      -39-


<PAGE>



in respect of taxes are, in the judgment of the Borrower,
adequate.

                  (k) Financial Statements. The Borrower has furnished or caused
to be furnished to the  Administrative  Agent and the Banks as of the  Agreement
Date,  the audited  financial  statements  for  American  Radio  Systems and its
Subsidiaries  on a  consolidated  basis for the fiscal year ended  December  31,
1995,  and unaudited  financial  statements  for the Borrower and its Restricted
Subsidiaries  for the fiscal quarter ended June 30, 1996, all of which have been
prepared in accordance with GAAP and present fairly in all material respects the
financial  position  of  the  Borrower  and  its  Restricted  Subsidiaries  on a
consolidated  basis,  on and as at such dates and the results of operations  for
the periods then ended (subject,  in the case of unaudited financial statements,
to normal year-end and audit  adjustments).  Neither the Borrower nor any of its
Restricted  Subsidiaries has any material liabilities,  contingent or otherwise,
other than as disclosed in the financial statements referred to in the preceding
sentence or as set forth or referred to in this Agreement.

                  (l) No Material  Adverse  Change.  There has occurred no event
since June 30,  1996 which has or which could  reasonably  be expected to have a
Materially Adverse Effect.

                  (m) ERISA.  The Borrower and each  Subsidiary  of the Borrower
and each of their respective Plans are in compliance with ERISA and the Code and
neither  the  Borrower  nor  any  of  its  ERISA   Affiliates,   including   its
Subsidiaries,  has incurred any accumulated  funding  deficiency with respect to
any such Plan within the meaning of ERISA or the Code. The Borrower, each of its
Subsidiaries,  and each other ERISA  Affiliate  have  complied  in all  material
respects  with all  requirements  of COBRA.  Neither the Borrower nor any of its
Subsidiaries has made any promises of retirement or other benefits to employees,
except as set forth in the Plans, in written agreements with such employees,  or
in the  Borrower's  employee  handbook and memoranda to  employees.  Neither the
Borrower  nor any of its  ERISA  Affiliates,  including  its  Subsidiaries,  has
incurred any material  liability to PBGC in connection  with any such Plan.  The
assets of each such Plan which is subject to Title IV of ERISA are sufficient to
provide the benefits under such Plan, the payment of which PBGC would  guarantee
if such Plan were terminated, and such assets are also sufficient to provide all
other  "benefit  liabilities"  (within the meaning of Section 4041 of ERISA) due
under  the Plan upon  termination.  No  Reportable  Event  has  occurred  and is
continuing  with  respect  to any  such  Plan.  No such  Plan or  trust  created
thereunder,  or party in interest (as defined in Section 3(14) of ERISA), or any
fiduciary (as defined in Section  3(21) of ERISA),  has engaged in a "prohibited
transaction" (as such term is


                                      -40-


<PAGE>



defined in Section 406 of ERISA or Section 4975 of the Code) which would subject
such Plan or any other  Plan of the  Borrower  or any of its  Subsidiaries,  any
trust created  thereunder,  or any such party in interest or  fiduciary,  or any
party  dealing  with any such Plan or any such  trust,  to the tax or penalty on
"prohibited transactions" imposed by Section 502 of ERISA or Section 4975 of the
Code.  Neither  the  Borrower  nor any of its ERISA  Affiliates,  including  its
Subsidiaries,  is or has been  obligated to make any payment to a  Multiemployer
Plan.

                  (n)  Compliance  with  Regulations  G, T, U and X. Neither the
Borrower  nor  any  of  the  Borrower's   Restricted   Subsidiaries  is  engaged
principally  or as one of its important  activities in the business of extending
credit for the purpose of purchasing  or carrying,  and neither the Borrower nor
any of the  Borrower's  Restricted  Subsidiaries  owns or  presently  intends to
acquire, any "margin security" or "margin stock" as defined in Regulations G, T,
U, and X (12 C.F.R.  Parts 207,  220,  221 and 224) of the Board of Governors of
the Federal Reserve System (herein called "margin stock").  None of the proceeds
of the Loans will be used, directly or indirectly, for the purpose of purchasing
or carrying  any margin  stock or for the  purpose of  reducing or retiring  any
Indebtedness which was originally  incurred to purchase or carry margin stock or
for any other purpose which might constitute this transaction a "purpose credit"
within the  meaning of said  Regulations  G, T, U, and X. The  Borrower  has not
taken,  caused or  authorized  to be taken,  and will not take any action  which
might cause this  Agreement or the Notes to violate  Regulation G, T, U, or X or
any other  regulation of the Board of Governors of the Federal Reserve System or
to violate the Securities Exchange Act of 1934, in each case as now in effect or
as the same may  hereafter be in effect.  If so requested by the  Administrative
Agent, the Borrower will furnish the  Administrative  Agent with (i) a statement
or statements in conformity  with the  requirements of Federal Reserve Forms G-3
and/or U-1 referred to in  Regulations  G and U of said Board of  Governors  and
(ii) other  documents  evidencing  its compliance  with the margin  regulations,
reasonably  requested  by the  Administrative  Agent.  Neither the making of the
Loans nor the use of proceeds thereof will violate, or be inconsistent with, the
provisions of Regulation G, T, U, or X of said Board of Governors.

                  (o)  Investment  Company Act.  Neither the Borrower nor any of
its Restricted  Subsidiaries is required to register under the provisions of the
Investment  Company Act of 1940,  as amended,  and neither the entering  into or
performance  by the Borrower and its Restricted  Subsidiaries  of this Agreement
and the Loan  Documents nor the issuance of the Notes  violates any provision of
such Act or requires any consent,  approval or authorization of, or registration
with, the Securities and Exchange Commission or


                                      -41-


<PAGE>



any other governmental or public body or authority pursuant to
any provisions of such Act.

                  (p) Governmental  Regulation.  Neither the Borrower nor any of
its  Restricted  Subsidiaries  is  required  to obtain  any  consent,  approval,
authorization,  permit or license which has not already been  obtained  from, or
effect any filing or registration  which has not already been effected with, any
federal,  state or local  regulatory  authority in connection with the execution
and delivery of this Agreement or any other Loan Document.  Neither the Borrower
nor any of its  Restricted  Subsidiaries  is  required  to obtain  any  consent,
approval,  authorization,  permit or license which has not already been obtained
from, or effect any filing or  registration  which has not already been effected
with, any federal,  state or local  regulatory  authority in connection with the
performance, in accordance with their respective terms, of this Agreement or any
other Loan Document,  other than filing of appropriate UCC financing  statements
and mortgages.

                  (q) Absence of Default,  Etc. The Borrower and its  Restricted
Subsidiaries  are in compliance  in all respects  with all of the  provisions of
their   respective   partnership   agreements,   Certificates   or  Articles  of
Incorporation  and  By-Laws,  as the case may be, and no event has  occurred  or
failed to occur (including,  without limitation, any matter which could create a
Default hereunder by cross-default)  which has not been remedied or waived,  the
occurrence  or  non-occurrence  of which  constitutes,  (i) a Default  or (ii) a
material default by the Borrower or any of its Restricted Subsidiaries under any
indenture,  agreement  or  other  instrument  relating  to  Indebtedness  of the
Borrower or any of its  Restricted  Subsidiaries  in the amount of $1,000,000 or
more in the aggregate, any material License, or any judgment, decree or order to
which the Borrower or any of its Restricted  Subsidiaries is a party or by which
the Borrower or any of its Restricted  Subsidiaries  or any of their  respective
properties may be bound or affected.

                  (r) Accuracy and Completeness of Information. All information,
reports,  prospectuses and other papers and data relating to the Borrower or any
of its Restricted  Subsidiaries and furnished by or on behalf of the Borrower or
any of its Restricted  Subsidiaries  to the  Administrative  Agent or the Banks,
taken as a whole, were, at the time furnished, true, complete and correct in all
material respects to the extent necessary to give the  Administrative  Agent and
the  Banks  true  and  accurate   knowledge  of  the  subject  matter,  and  all
projections,  consisting of a  consolidated  projected cash flow  statement,  an
income  statement,   and  a  balance  sheet  for  Borrower  and  its  Restricted
Subsidiaries (the  "Projections") (i) disclose all assumptions made with respect
to costs,  general  economic  conditions,  and financial  and market  conditions
formulating the Projections; (ii)


                                      -42-


<PAGE>



are based on reasonable estimates and assumptions;  and (iii) reflect, as of the
date prepared,  and continue to reflect,  as of the date hereof,  the reasonable
estimate  of  Borrower  of the  results  of  operations  and  other  information
projected therein for the periods covered thereby.

                  (s)  Agreements  with  Affiliates.  Except for  agreements  or
arrangements  with  Affiliates  wherein  the  Borrower  or  one or  more  of its
Restricted   Subsidiaries   provides   services  to  such  Affiliates  for  fair
consideration or which are set forth on Schedule 4.1(s) attached hereto, neither
the  Borrower  nor  any of its  Restricted  Subsidiaries  has  (i)  any  written
agreements  or binding  arrangements  of any kind with any Affiliate or (ii) any
management or consulting  agreements of any kind with any Affiliate,  other than
those between the Borrower and its Restricted Subsidiaries.

                  (t) Payment of Wages.  The Borrower and each of its Restricted
Subsidiaries are in compliance with the Fair Labor Standards Act, as amended, in
all  material  respects,  and to the  knowledge  of the Borrower and each of its
Subsidiaries,  such Persons have paid all minimum and overtime wages required by
law to be paid to their respective employees.

                  (u)  Priority.  The  Security  Interest  is a valid and,  upon
filing of  appropriate  UCC financing  statements  and/or  mortgages,  will be a
perfected  first  priority  security  interest in the Collateral in favor of the
Administrative  Agent,  for the  benefit of itself and the Banks,  securing,  in
accordance with the terms of the Security  Documents,  the Obligations,  and the
Collateral is subject to no Liens other than Permitted  Liens. The Liens created
by the Security  Documents are  enforceable  as security for the  Obligations in
accordance  with their  terms  with  respect to the  Collateral  subject,  as to
enforcement  of  remedies,  to the  following  qualifications:  (i) an  order of
specific  performance  and an  injunction  are  discretionary  remedies  and, in
particular, may not be available where damages are considered an adequate remedy
at  law,  and  (ii)  enforcement  may  be  limited  by  bankruptcy,  insolvency,
liquidation,  reorganization,  reconstruction  and other similar laws  affecting
enforcement of creditors'  rights generally  (insofar as any such law relates to
the  bankruptcy,  insolvency  or  similar  event of the  Borrower  or any of its
Subsidiaries, as the case may be).

                  (v) Indebtedness.  Except as shown on the financial statements
of Borrower  for the fiscal  quarter  ended June 30,  1996,  or as  described on
Schedule  4.1(v)  attached hereto neither the Borrower nor any of its Restricted
Subsidiaries has outstanding,  as of the Agreement Date, and after giving effect
to the initial  Advances  hereunder on the Agreement Date, any  Indebtedness for
Money Borrowed.


                                      -43-


<PAGE>




                  (w) Solvency. As of the Agreement Date and after giving effect
to the  transactions  contemplated by the Loan Documents (i) the property of the
Borrower,  at a fair  valuation,  will exceed its debt;  (ii) the capital of the
Borrower  will not be  unreasonably  small to conduct  its  business;  (iii) the
Borrower will not have incurred debts,  or have intended to incur debts,  beyond
its ability to pay such debts as they mature;  and (iv) the present fair salable
value of the assets of the Borrower will be greater than the amount that will be
required  to pay its  probable  liabilities  (including  debts)  as they  become
absolute and matured.  For purposes of this Section,  "debt" means any liability
on a claim,  and  "claim"  means (i) the right to  payment,  whether or not such
right is reduced  to  judgment,  liquidated,  unliquidated,  fixed,  contingent,
matured, unmatured,  undisputed, legal, equitable, secured or unsecured, or (ii)
the right to an equitable  remedy for breach of performance if such breach gives
rise to a right to payment,  whether or not such right to an equitable remedy is
reduced to judgment, fixed, contingent, matured, unmatured,  undisputed, secured
or unsecured.

         Section 4.2  Survival  of  Representations  and  Warranties,  etc.  All
representations  and  warranties  made under this  Agreement  and any other Loan
Document  shall be  deemed  to be made,  and  shall be true and  correct  in all
material  respects,  at and as of the  Agreement  Date  and on the  date of each
Advance except to the extent  relating  specifically  to the Agreement Date. All
representations  and  warranties  made under this  Agreement  and the other Loan
Documents shall survive, and not be waived by, the execution hereof by the Banks
and the  Administrative  Agent, any  investigation or inquiry by any Bank or the
Administrative Agent, or the making of any Advance under this Agreement.


                                    ARTICLE 5

                                General Covenants

         So long as any of the  Obligations  is  outstanding  and  unpaid or the
Banks  have  an  obligation  to  fund  Advances  hereunder  (whether  or not the
conditions to borrowing have been or can be fulfilled),  and unless the Majority
Banks,  or such  greater  number of Banks as may be expressly  provided  herein,
shall otherwise consent in writing:

         Section 5.1  Preservation of Existence and Similar  Matters.  Except as
permitted  under Section 7.4 hereof,  the Borrower  will, and will cause each of
its Restricted Subsidiaries to:

                  (i)  preserve and  maintain  its  existence,  and its material
         rights, franchises, licenses and privileges in the


                                      -44-


<PAGE>



         state of its incorporation, including, without limiting the
         foregoing, the Licenses and all other Necessary
         Authorizations; and

                        (ii) qualify and remain  qualified and  authorized to do
         business in each  jurisdiction in which the character of its properties
         or  the  nature  of  its  business   requires  such   qualification  or
         authorization,  except  for  such  failure  to  so  qualify  and  be so
         authorized  as could not  reasonably  be  expected  to have a  Material
         Adverse Effect.

         Section 5.2  Business;  Compliance  with  Applicable  Law. The Borrower
will, and will cause each of its Restricted  Subsidiaries  to, (a) engage in the
business  of  owning,   constructing,   managing,  operating  and  investing  in
communications   tower  facilities  and  related  businesses  and  no  unrelated
activities, and (b) comply in all material respects with the requirements of all
Applicable Law.

         Section 5.3  Maintenance  of  Properties.  The Borrower  will, and will
cause each of its Restricted Subsidiaries to, maintain or cause to be maintained
in the ordinary  course of business in good repair,  working order and condition
(reasonable  wear and tear  excepted) all  properties  used in their  respective
businesses (whether owned or held under lease), other than obsolete equipment or
unused  assets  and from  time to time make or cause to be made all  needed  and
appropriate  repairs,  renewals,   replacements,   additions,   betterments  and
improvements thereto.

         Section 5.4  Accounting  Methods and  Financial  Records.  The Borrower
will, and will cause each of its Restricted  Subsidiaries on a consolidated  and
consolidating  basis  to,  maintain  a  system  of  accounting  established  and
administered in accordance with GAAP, keep adequate records and books of account
in which  complete  entries will be made in accordance  with GAAP and reflecting
all transactions required to be reflected by GAAP and keep accurate and complete
records  of  their  respective  properties  and  assets.  The  Borrower  and its
Restricted Subsidiaries will maintain a fiscal year ending on December 31.

         Section 5.5  Insurance.  The Borrower  will, and will cause each of its
Restricted Subsidiaries to:

                  (a) Maintain insurance including, but not limited to, business
interruption  coverage and public liability  coverage insurance from responsible
companies in such amounts and against such risks to the Borrower and each of its
Restricted  Subsidiaries as is prudent for similarly  situated companies engaged
in the communications tower industry.



                                      -45-


<PAGE>



                  (b) Keep their respective  assets insured by insurers on terms
and in a manner reasonably  acceptable to the Administrative  Agent against loss
or damage by fire,  theft,  burglary,  loss in transit,  explosions  and hazards
insured  against by  extended  coverage,  in amounts  which are  prudent for the
communications   tower   management   and  operation   industry  and  reasonably
satisfactory to the Administrative Agent, all premiums thereon to be paid by the
Borrower and its Restricted Subsidiaries.

                  (c) Require that each  insurance  policy  provide for at least
thirty  (30)  days'  prior  written  notice to the  Administrative  Agent of any
termination of or proposed  cancellation or nonrenewal of such policy,  and name
the  Administrative  Agent  as  additional  named  lender  loss  payee  and,  as
appropriate, additional insured, to the extent of the Obligations.

         Section 5.6 Payment of Taxes and Claims.  The Borrower  will,  and will
cause  each of its  Restricted  Subsidiaries  to, pay and  discharge  all taxes,
including,  without limitation,  withholding taxes, assessments and governmental
charges  or levies  required  to be paid by them or  imposed  upon them or their
income or profits or upon any properties belonging to them, prior to the date on
which penalties attach thereto,  and all lawful claims for labor,  materials and
supplies  which,  if  unpaid,  might  become a Lien or charge  upon any of their
properties;  except that no such tax, assessment,  charge, levy or claim need be
paid  which  is  being  diligently   contested  in  good  faith  by  appropriate
proceedings  and for which  adequate  reserves  shall have been set aside on the
appropriate  books, but only so long as such tax,  assessment,  charge,  levy or
claim  does not  become a Lien or  charge  other  than a  Permitted  Lien and no
foreclosure,  distraint,  sale or similar proceedings shall have been commenced.
The Borrower will, and will cause each of its Restricted Subsidiaries to, timely
file  all  information   returns  required  by  federal,   state  or  local  tax
authorities.

         Section 5.7 Compliance with ERISA.

                  (a) The Borrower shall,  and shall cause its  Subsidiaries to,
make all contributions to any Employee Pension Plan when such  contributions are
due and not incur any  "accumulated  funding  deficiency"  within the meaning of
Section 412(a) of the Code,  whether or not waived,  and will  otherwise  comply
with the requirements of the Code and ERISA with respect to the operation of all
Plans,  except to the  extent  that the  failure  to so comply  could not have a
Materially Adverse Effect.



                                      -46-


<PAGE>



                  (b) The Borrower shall,  and shall cause its  Subsidiaries to,
comply in all respects with the  requirements of COBRA with respect to any Plans
subject to the requirements thereof, except to the extent that the failure to so
comply could not have a Materially Adverse Effect.

                  (c) The Borrower  shall  furnish to  Administrative  Agent (i)
within 30 days  after any  officer  of the  Borrower  obtains  knowledge  that a
"prohibited  transaction" (within the meaning of Section 406 of ERISA or Section
4975 of the Code) has  occurred  with respect to any Plan of the Borrower or its
ERISA  Affiliates,  including its  Subsidiaries,  that any Reportable  Event has
occurred with respect to any Employee  Pension Plan or that PBGC has  instituted
or will institute  proceedings under Title IV of ERISA to terminate any Employee
Pension Plan or to appoint a trustee to administer any Employee  Pension Plan, a
statement  setting  forth  the  details  as  to  such  prohibited   transaction,
Reportable Event or termination or appointment  proceedings and the action which
it (or any other  Employee  Pension  Plan  sponsor if other  than the  Borrower)
proposes to take with  respect  thereto,  together  with a copy of the notice of
such Reportable Event given to PBGC if a copy of such notice is available to the
Borrower, any of its Subsidiaries or any of its ERISA Affiliates,  (ii) promptly
after  receipt  thereof,  a  copy  of  any  notice  the  Borrower,  any  of  its
Subsidiaries or any of its ERISA  Affiliates or the sponsor of any Plan receives
from PBGC, or the Internal Revenue Service or the Department of Labor which sets
forth or proposes any action or  determination  with respect to such Plan, (iii)
promptly  after the filing  thereof,  any  annual  report  required  to be filed
pursuant to ERISA in connection with each Plan maintained by the Borrower or any
of its ERISA Affiliates,  including the Subsidiaries, and (iv) promptly upon the
Administrative Agent's request therefor,  such additional information concerning
any such Plan as may be reasonably requested by the Administrative Agent.

                  (d) The Borrower will promptly notify the Administrative Agent
of any excise taxes which have been assessed or which the  Borrower,  any of its
Subsidiaries  or any of its  ERISA  Affiliates  has  reason  to  believe  may be
assessed  against  the  Borrower,  any of its  Subsidiaries  or any of its ERISA
Affiliates  by the  Internal  Revenue  Service or the  Department  of Labor with
respect  to any Plan of the  Borrower  or its ERISA  Affiliates,  including  its
Subsidiaries.

                  (e)  Within  the time  required  for  notice to the PBGC under
Section 302(f)(4)(A) of ERISA, the Borrower will notify the Administrative Agent
of any lien arising  under  Section  302(f) of ERISA in favor of any Plan of the
Borrower or its ERISA Affiliates, including its Subsidiaries.



                                      -47-


<PAGE>



                  (f) The  Borrower  will not,  and will not  permit  any of its
Subsidiaries or any of its ERISA Affiliates to take any of the following actions
or permit any of the following  events to occur if such action or event together
with all other such actions or events  would  subject the  Borrower,  any of its
Subsidiaries,  or any of its  ERISA  Affiliates  to any tax,  penalty,  or other
liabilities which could have a Materially Adverse Effect:

                         (i) engage in any  transaction in connection with which
         the Borrower,  any of its  Subsidiaries or any ERISA Affiliate could be
         subject to either a civil penalty  assessed  pursuant to Section 502(i)
         of ERISA or a tax imposed by Section 4975 of the Code;

                        (ii) terminate any Employee Pension Plan in a manner, or
         take any other  action,  which  could  result in any  liability  of the
         Borrower, any of its Subsidiaries or any ERISA Affiliate to the PBGC;

                       (iii) fail to make full  payment  when due of all amounts
         which,  under the  provisions  of any Plan,  the  Borrower,  any of its
         Subsidiaries or any ERISA Affiliate is required to pay as contributions
         thereto,  or permit to exist any accumulated  funding deficiency within
         the meaning of Section 412(a) of the Code, whether or not waived,  with
         respect to any Employee Pension Plan; or

                        (iv) permit the present value of all benefit liabilities
         under all Employee Pension Plans which are subject to Title IV of ERISA
         to exceed the present  value of the assets of such Plans  allocable  to
         such benefit liabilities (within the meaning of Section 4041 of ERISA),
         except as may be permitted under actuarial funding standards adopted in
         accordance with Section 412 of the Code.

         Section 5.8 Visits and  Inspections.  The Borrower will, and will cause
each  of  its  Restricted   Subsidiaries  to,  permit   representatives  of  the
Administrative  Agent and any of the Banks, upon reasonable notice, to (i) visit
and inspect the properties of the Borrower or any of its Restricted Subsidiaries
during business  hours,  (ii) inspect and make extracts from and copies of their
respective books and records,  and (iii) discuss with their respective principal
officers their respective businesses, assets, liabilities,  financial positions,
results of  operations  and  business  prospects.  The  Borrower and each of its
Restricted  Subsidiaries will also permit  representatives of the Administrative
Agent and any of the Banks to discuss  with  their  respective  accountants  the
Borrower's  and the  Borrower's  Restricted  Subsidiaries'  businesses,  assets,
liabilities,


                                      -48-


<PAGE>



financial positions, results of operations and business
prospects.

         Section 5.9 Payment of Indebtedness;  Loans.  Subject to any provisions
herein or in any other Loan Document,  the Borrower will, and will cause each of
its Restricted Subsidiaries to, pay any and all of their respective Indebtedness
when and as it becomes due, other than amounts diligently disputed in good faith
and for which adequate reserves have been set aside in accordance with GAAP.

         Section  5.10 Use of  Proceeds.  The  Borrower  will use the  aggregate
proceeds of all Advances under the Loans directly or indirectly:

                  (a) to fund Acquisitions permitted by Section 7.6 hereof;

                  (b) to fund Capital Expenditures to the extent permitted under
Section 7.11 hereof; and

                  (c) for working capital needs and other corporate  purposes of
the Borrower and its Restricted Subsidiaries (including, without limitation, the
fees and expenses incurred in connection with the execution and delivery of this
Agreement) which do not otherwise conflict with this Section 5.10.

No proceeds of Advances  hereunder shall be used for the purchase or carrying or
the extension of credit for the purpose of  purchasing  or carrying,  any margin
stock within the meaning of Regulations G, T, U, and X of the Board of Governors
of the Federal Reserve System.

         Section  5.11 Real  Estate.  The  Borrower  shall,  and shall cause its
Restricted  Subsidiaries  to, on the Agreement  Date,  and,  thereafter,  within
thirty (30) days of the  acquisition of any real estate  permitted under Section
7.13  hereof,  grant  a  mortgage  to  the  Administrative  Agent  securing  the
Obligations (or such amount thereof as is equal to the fair market value of such
real estate if the Majority Banks so permit),  in form and substance  reasonably
satisfactory to the Administrative  Agent, covering any parcel of real estate as
may be owned by the Borrower or any of its  Restricted  Subsidiaries;  provided,
that (a) this Section 5.11 shall not apply to the  Philadelphia  Disposition and
(b) any real estate so acquired  that is incidental  to such  Acquisition  or is
otherwise  incidental  to or not  useful in the  business  of  Borrower  or such
Restricted  Subsidiary,  Borrower may notify the Administrative Agent in writing
that it or such  Restricted  Subsidiary  intends to,  subject to Section  2.5(c)
hereof,  sell  such  real  estate  within  eight  (8)  months of the date of the
acquisition thereof, in which case, the mortgage required to be


                                      -49-


<PAGE>



granted  pursuant to this  Section  5.11 need not be  granted,  but if such real
estate is not sold in such eight (8) month period,  Borrower or such  Restricted
Subsidiary  shall, on the first Business Day following the end of such eight (8)
month  period,  grant a  mortgage  with  respect  to  such  real  estate  to the
Administrative  Agent as required and in accordance  with this Section 5.11. The
Borrower shall,  and shall cause its Restricted  Subsidiaries to, deliver to the
Administrative  Agent all  documentation,  including  opinions  of  counsel  and
policies  of  title   insurance,   which  in  the  reasonable   opinion  of  the
Administrative Agent are appropriate with each such grant, including any phase I
environmental audit requested by the Majority Banks.

         Section  5.12  Indemnity.  The Borrower  agrees to  indemnify  and hold
harmless  each Bank,  the  Administrative  Agent,  and each of their  respective
affiliates,  employees,  representatives,  shareholders,  officers and directors
(any of the  foregoing  shall be an  "Indemnitee")  from and against any and all
claims,  liabilities,  losses, damages, actions,  reasonable attorneys' fees and
expenses  (as such fees and  expenses  are  incurred)  and demands by any party,
including the costs of investigating  and defending such claims,  whether or not
the Borrower, any Restricted Subsidiary or the Person seeking indemnification is
the  prevailing  party (a)  resulting  from any breach or alleged  breach by the
Borrower or any Restricted  Subsidiary of the Borrower of any  representation or
warranty made hereunder;  or (b) otherwise  arising out of (i) the Commitment or
otherwise   under  this   Agreement,   any  Loan  Document  or  any  transaction
contemplated hereby or thereby,  including,  without limitation,  the use of the
proceeds of Loans hereunder in any fashion by the Borrower or the performance of
their respective  obligations under the Loan Documents by the Borrower or any of
its Restricted Subsidiaries, (ii) allegations of any participation by the Banks,
the Administrative  Agent, or any of them, in the affairs of the Borrower or any
of its  Subsidiaries,  or allegations  that any of them has any joint  liability
with the Borrower or any of its Restricted  Subsidiaries  for any reason,  (iii)
any claims against the Banks, the  Administrative  Agent, or any of them, by any
shareholder  or other  investor in or lender to the  Borrower or any  Restricted
Subsidiary,  by any  brokers or finders or  investment  advisers  or  investment
bankers retained by the Borrower or by any other third party, arising out of the
Commitment or otherwise  under this  Agreement;  or (c) in connection with taxes
(not including  federal or state income or franchise  taxes or other taxes based
solely upon the revenues or income of such  Persons),  fees,  and other  charges
payable  in  connection  with  the  Loans,  or  the  execution,   delivery,  and
enforcement of this Agreement, the Security Documents, the other Loan Documents,
and any amendments thereto or waivers of any of the provisions  thereof;  unless
the Person seeking indemnification hereunder is determined in such


                                      -50-


<PAGE>



case to have acted with gross negligence or willful misconduct,  in any case, by
a final,  non-appealable  judicial order.  The obligations of the Borrower under
this  Section  5.12 are in  addition  to,  and shall not  otherwise  limit,  any
liabilities  which the Borrower  might  otherwise  have in  connection  with any
warranties or similar obligations of the Borrower in any other Loan Document.

         Section  5.13  Interest  Rate  Hedging.  Within  sixty (60) days of the
Agreement Date and forty-five  (45) days after each Advance,  the Borrower shall
enter into (and shall at all times thereafter  maintain for a period of not less
than two (2) years) one or more Interest  Hedge  Agreements  with respect to the
Borrower's  interest  obligations  on not less than fifty  percent  (50%) of the
principal amount of the Loans outstanding from time to time. Such Interest Hedge
Agreements   shall  provide   interest  rate   protection  in  conformity   with
International Swap Dealers Association standards and for an average period of at
least two (2)  years  from the date of such  Interest  Hedge  Agreements  or, if
earlier,  until  the  Maturity  Date  on  terms  reasonably  acceptable  to  the
Administrative   Agent,   such   terms   to   include   consideration   of   the
creditworthiness  of the other party to the proposed  Interest Hedge  Agreement.
All  Obligations  of the Borrower to either  Administrative  Agent or any of the
Banks pursuant to any Interest  Hedge  Agreement and all Liens granted to secure
such  Obligations  shall rank pari passu  with all other  Obligations  and Liens
securing such other  Obligations;  and any Interest Hedge Agreement  between the
Borrower and any other Person shall be unsecured.

         Section 5.14 Covenants Regarding  Formation of Restricted  Subsidiaries
and Acquisitions;  Partnership, Subsidiaries. At the time of (i) any Acquisition
permitted hereunder,  (ii) the purchase by the Borrower or any of its Restricted
Subsidiaries  of any interests in any Restricted or  Unrestricted  Subsidiary of
the  Borrower,  or (iii) the  formation of any new  Restricted  or  Unrestricted
Subsidiary  of the  Borrower  or any of its  Restricted  Subsidiaries  which  is
permitted under this Agreement, the Borrower will, and will cause its Restricted
Subsidiaries,  as  appropriate,  to (a) provide to the  Administrative  Agent an
executed  Subsidiary  Security Agreement for any new Restricted  Subsidiary,  in
substantially  the form of Exhibit I attached hereto,  together with appropriate
UCC-1 financing statements,  as well as an executed Subsidiary Guaranty for such
new  Restricted  Subsidiary,  in  substantially  the form of  Exhibit G attached
hereto,  which shall  constitute both Security  Documents and Loan Documents for
purposes  of  this  Agreement,  as  well  as a loan  certificate  for  such  new
Restricted  Subsidiary,  substantially in the form of Exhibit L attached hereto,
together with appropriate  attachments;  (b) pledge to the Administrative  Agent
all of the stock or partnership interests (or other instruments or


                                      -51-


<PAGE>



securities  evidencing ownership) of such Subsidiary or Person which is acquired
or  formed,  beneficially  owned  by the  Borrower  or  any  of  the  Borrower's
Restricted  Subsidiaries,  as the case may be, as additional  Collateral for the
Obligations to be held by the Administrative  Agent in accordance with the terms
of the Borrower's  Pledge  Agreement,  or a new Subsidiary  Pledge  Agreement in
substantially the form of Exhibit H attached hereto,  and execute and deliver to
the  Administrative  Agent all such  documentation  for such  pledge  as, in the
reasonable  opinion of the  Administrative  Agent, is appropriate;  and (c) with
respect to any Acquisition or Restricted  Subsidiary,  provide revised financial
projections  for the remainder of the fiscal year and for each  subsequent  year
until the Maturity Date which reflect such  Acquisition or formation,  certified
by the Chief  Financial  Officer of the  Borrower,  together with a statement by
such Person  that no Default  exists or would be caused by such  Acquisition  or
formation,  and all  other  documentation,  including  one or more  opinions  of
counsel,  reasonably  satisfactory  to the  Administrative  Agent which in their
reasonable  opinion  is  appropriate  with  respect to such  Acquisition  or the
formation of such Subsidiary.  Notwithstanding the foregoing, the Borrower shall
not be required to pledge any of the stock or other ownership  interests for any
Unrestricted  Subsidiary  which (x) was not formed or created in anticipation of
the Borrower's  direct or indirect  investment  therein and (y) at the time such
stock or  ownership  interest  was  acquired by the  Borrower or its  Restricted
Subsidiaries  is  subject  to a  restriction  on any  such  Lien  (whether  such
restriction is in such Person's formation documents or otherwise),  but shall be
required to grant the Administrative Agent (for the benefit of the Banks) a Lien
upon any right to receive distributions from such Unrestricted  Subsidiary.  Any
document,  agreement  or  instrument  (other than the  Projections)  executed or
issued  pursuant to this Section 5.14 shall be a "Loan Document" for purposes of
this Agreement.

         Section 5.15 Payment of Wages.  The Borrower shall and shall cause each
of its Restricted Subsidiaries to at all times comply, in all material respects,
with the  material  requirements  of the Fair Labor  Standards  Act, as amended,
including,  without  limitation,  the  provisions  of such Act  relating  to the
payment of minimum  and  overtime  wages as the same may become due from time to
time.

         Section 5.16 Further  Assurances.  The Borrower will promptly  cure, or
cause to be cured,  defects in the creation and issuance of any of the Notes and
the execution and delivery of the Loan  Documents  (including  this  Agreement),
resulting  from  any  acts  or  failure  to act by  the  Borrower  or any of the
Borrower's  Restricted  Subsidiaries  or any  employee or officer  thereof.  The
Borrower at its expense will promptly execute and deliver to the  Administrative
Agent and the Banks, or cause to be executed and


                                      -52-


<PAGE>



delivered to the Administrative  Agent and the Banks, all such other and further
documents,  agreements,  and instruments in compliance with or accomplishment of
the covenants and  agreements of the Borrower in the Loan  Documents,  including
this Agreement, or to correct any omissions in the Loan Documents, or more fully
to state the obligations  set out herein or in any of the Loan Documents,  or to
obtain any  consents,  all as may be  necessary  or  appropriate  in  connection
therewith and as may be reasonably requested.


                                    ARTICLE 6

                              Information Covenants

         So long as any of the  Obligations  is  outstanding  and  unpaid or the
Banks  have  an  obligation  to  fund  Advances  hereunder  (whether  or not the
conditions to borrowing  have been or can be fulfilled)  and unless the Majority
Banks shall otherwise consent in writing,  the Borrower will furnish or cause to
be  furnished to each Bank and the  Administrative  Agent,  at their  respective
offices:

         Section 6.1 Quarterly  Financial  Statements  and  Information.  Within
forty-five  (45) days after the last day of each of the first three (3) quarters
of each fiscal year of the  Borrower,  the balance  sheets of the  Borrower on a
consolidated  basis with its Restricted  Subsidiaries and a consolidating  basis
with its  Unrestricted  Subsidiaries as at the end of such quarter and as of the
end of the preceding  fiscal year, and the related  statements of operations and
the related  statements  of cash flows of the Borrower on a  consolidated  basis
with its Restricted Subsidiaries and a consolidating basis with its Unrestricted
Subsidiaries for such quarter and for the elapsed portion of the year ended with
the last day of such  quarter,  which shall set forth in  comparative  form such
figures as at the end of and for such quarter and  appropriate  prior period and
shall be certified by the chief  financial  officer of the Borrower to have been
prepared in accordance with GAAP and to present fairly in all material  respects
the  financial  position  of the  Borrower  on a  consolidated  basis  with  its
Restricted   Subsidiaries  and  a  consolidating  basis  with  its  Unrestricted
Subsidiaries as at the end of such period and the results of operations for such
period,  and for the elapsed portion of the year ended with the last day of such
period, subject only to normal year-end and audit adjustments.

         Section 6.2                Annual Financial Statements and Information.
Within ninety (90) days after the end of each fiscal year of the
Borrower, the audited consolidated balance sheet of the Borrower
and its Restricted Subsidiaries (and unaudited consolidating


                                      -53-


<PAGE>



balance sheet of the Borrower and its  Unrestricted  Subsidiaries) as of the end
of  such  fiscal  year  and  the  related  audited  consolidated  and  unaudited
consolidating statements of operations for such fiscal year and for the previous
fiscal  year,  the  related  audited  consolidated  statements  of cash flow and
stockholders'  equity for such fiscal  year and for the  previous  fiscal  year,
which shall be  accompanied  by an opinion which shall be in scope and substance
reasonably satisfactory to the Administrative Agent of Deloitte & Touche, LLP or
other independent  certified public accountants of recognized  national standing
reasonably  acceptable to the Administrative Agent, together with a statement of
such  accountants  that in  connection  with their audit,  nothing came to their
attention  that caused them to believe that the  Borrower was not in  compliance
with the terms,  covenants,  provisions or conditions of Sections 7.8, 7.9, 7.10
and 7.11 hereof insofar as they relate to accounting matters.

         Section  6.3  Performance  Certificates.  At  the  time  the  financial
statements are furnished  pursuant to Sections 6.1 and 6.2, a certificate of the
president  or  chief  financial  officer  of the  Borrower  as to its  financial
performance, in substantially the form attached hereto as Exhibit M:

                  (a) setting forth as and at the end of such  quarterly  period
or fiscal year, as the case may be, the  arithmetical  calculations  required to
establish  (i) any  adjustment  to the  Applicable  Margins,  as provided for in
Section 2.3(f),  and (ii) whether or not the Borrower was in compliance with the
requirements of Sections 7.7, 7.8, 7.9, 7.10 and 7.11;

                  (b)  stating  that,  to the best of his or her  knowledge,  no
Default has occurred as at the end of such quarterly period or year, as the case
may be, or, if a Default  has  occurred,  disclosing  each such  Default and its
nature, when it occurred,  whether it is continuing and the steps being taken by
the Borrower with respect to such Default; and

                  (c)  containing  a  list  of  all  Acquisitions,  Investments,
Restricted  Payments and  dispositions of assets from the Agreement Date through
the date of such  certificate,  together  with the total  amount for each of the
foregoing categories.

         Section 6.4 Copies of Other Reports.

                  (a) Promptly upon receipt thereof,  copies of all reports,  if
any, submitted to the Borrower by the Borrower's  independent public accountants
regarding the Borrower,  including,  without  limitation,  any management report
prepared in connection with the annual audit referred to in Section 6.2.



                                      -54-


<PAGE>



                  (b)  Promptly  upon  receipt  thereof,  copies of any material
adverse notice or report regarding any License from the FCC.

                  (c) From time to time and  promptly  upon each  request,  such
data,  certificates,  reports,  statements,  documents  or  further  information
regarding the business, assets,  liabilities,  financial position,  projections,
results of  operations  or  business  prospects  of the  Borrower  or any of its
Restricted  Subsidiaries,  as  Administrative  Agent or any Bank may  reasonably
request.

                  (d) Annually,  certificates  of insurance  indicating that the
requirements  of Section  5.5 hereof  remain  satisfied  for such  fiscal  year,
together  with  copies of any new or  replacement  insurance  policies  obtained
during such year.

                  (e) Prior to January 31 of each  year,  the annual  budget for
the Borrower and the Borrower's Restricted Subsidiaries,  including forecasts of
the income statement, the balance sheet and a cash flow statement for such year,
on a quarter by quarter basis.

                  (f)  Promptly  after  the  sending  thereof,   copies  of  all
statements,  reports  and other  information  which the  Borrower  or any of its
Restricted  Subsidiaries  sends  to  public  security  holders  of the  Borrower
generally or files with the Securities  and Exchange  Commission or any national
securities exchange.

         Section 6.5 Notice of Litigation and Other Matters.  Notice  specifying
the nature and status of any of the following events, promptly, but in any event
not later than fifteen (15) days after the  occurrence  of any of the  following
events becomes known to the Borrower:

                         (i)   the   commencement   of   all   proceedings   and
         investigations  by or before any governmental  body and all actions and
         proceedings in any court or before any arbitrator  against the Borrower
         or any Restricted Subsidiary,  or, to the extent known to the Borrower,
         which could have a Material Adverse Effect;

                        (ii) any  material  adverse  change with  respect to the
         business,   assets,   liabilities,   financial  position,   results  of
         operations  or business  prospects of the  Borrower and its  Restricted
         Subsidiaries,  taken as a whole,  other than  changes  in the  ordinary
         course of  business  which  have not had and would  not  reasonably  be
         expected to have a Materially  Adverse Effect and other than changes in
         the industry in which Borrower or any of its Restricted


                                      -55-


<PAGE>



         Subsidiaries operate which would not reasonably be expected
         to have a Material Adverse Effect;

                        (iii) any material  adverse  amendment or change to  the
         projections or annual budget provided to the Banks by the Borrower;

                        (iv) any Default or the occurrence or  non-occurrence of
         any event (A) which  constitutes,  or which with the passage of time or
         giving of notice or both would  constitute a default by the Borrower or
         any Restricted  Subsidiary of the Borrower under any material agreement
         other than this  Agreement  and the other Loan  Documents  to which the
         Borrower or any  Restricted  Subsidiary  of the Borrower is party or by
         which any of their  respective  properties  may be bound,  or (B) which
         could  have  a  Materially  Adverse  Effect,  giving  in  each  case  a
         description thereof and specifying the action proposed to be taken with
         respect thereto;

                         (v)  the  occurrence  of  any  Reportable  Event  or  a
         "prohibited  transaction"  (as such term is defined  in Section  406 of
         ERISA or  Section  4975 of the Code)  with  respect  to any Plan of the
         Borrower or any of its  Subsidiaries  or the  institution or threatened
         institution  by PBGC of  proceedings  under  ERISA to  terminate  or to
         partially  terminate  any such Plan or the  commencement  or threatened
         commencement of any litigation  regarding any such Plan or naming it or
         the  trustee  of any such Plan with  respect to such Plan or any action
         taken by the  Borrower,  any  Subsidiary  of the  Borrower or any ERISA
         Affiliate of the Borrower to withdraw or  partially  withdraw  from any
         Plan or to terminate any Plan; and

                        (vi)  the  occurrence  of any  event  subsequent  to the
         Agreement Date which, if such event had occurred prior to the Agreement
         Date,  would have  constituted an exception to the  representation  and
         warranty in Section 4.1(m) of this Agreement.


                                    ARTICLE 7

                               Negative Covenants

         So long as any of the  Obligations  is  outstanding  and  unpaid or the
Banks  have  an  obligation  to  fund  Advances  hereunder  (whether  or not the
conditions to borrowing  have been or can be fulfilled)  and unless the Majority
Banks, or such greater number


                                      -56-


<PAGE>



of Banks as may be expressly  provided herein,  shall otherwise give their prior
consent in writing:

         Section 7.1  Indebtedness  of the  Borrower and its  Subsidiaries.  The
Borrower  shall not, and shall not permit any of its  Subsidiaries  to,  create,
assume,  incur or otherwise  become or remain obligated in respect of, or permit
to be outstanding, any Indebtedness except:

                  (a)      the Obligations;

                  (b)      accounts payable, accrued expenses (including taxes)
and customer advance payments incurred in the ordinary course of business;

                  (c)      Indebtedness secured by Permitted Liens;

                  (d)      obligations under Interest Hedge Agreements with
respect to the Loans;

                  (e)  Indebtedness  of the  Borrower  or any of its  Restricted
Subsidiaries to the Borrower or any other  Restricted  Subsidiary so long as the
corresponding  debt  instruments  are  pledged  to the  Administrative  Agent as
security  for the  Obligations  and such  Indebtedness  is  expressly  permitted
pursuant to Section 7.5 hereof;

                  (f)  Indebtedness  incurred  by any  Unrestricted  Subsidiary;
provided that such  Indebtedness  is  non-recourse to the Borrower or any of its
Restricted  Subsidiaries  and no Lien is placed on the  Borrower's or any of its
Restricted Subsidiaries' equity interests in such Unrestricted Subsidiary; and

                  (g)      Capitalized Lease Obligations not to exceed in the
aggregate at any one time outstanding $1,000,000.

         Section 7.2 Limitation on Liens.  The Borrower shall not, and shall not
permit any of its Restricted Subsidiaries to, create, assume, incur or permit to
exist or to be created,  assumed,  incurred or permitted  to exist,  directly or
indirectly,  any Lien on any of its  properties or assets,  whether now owned or
hereafter acquired, except for Permitted Liens.

         Section 7.3 Amendment and Waiver. The Borrower shall not, and shall not
permit any of its  Restricted  Subsidiaries  to, enter into any amendment of, or
agree to or accept or consent to any waiver of any of the material provisions of
its articles or  certificate  of  incorporation  or  partnership  agreement,  as
appropriate,  if the effect  thereof would be to adversely  affect the rights of
the Banks hereunder or under any Loan Document.



                                      -57-


<PAGE>



         Section 7.4 Liquidation, Merger or Disposition of Assets.

                  (a)  Disposition of Assets.  The Borrower shall not, and shall
not  permit any of its  Restricted  Subsidiaries  to, at any time  sell,  lease,
abandon,  or otherwise  dispose of any assets (other than assets  disposed of in
the  ordinary  course of business and other than the  Philadelphia  Disposition)
without the prior  written  consent of the Banks;  provided,  however,  that the
prior written consent of the Banks shall not be required for (i) the transfer of
assets  (including  cash  or  cash  equivalents)  among  the  Borrower  and  its
Restricted  Subsidiaries  (excluding Subsidiaries described in clause (b) of the
definition of  "Subsidiary")  or for the transfer of assets  (including  cash or
cash   equivalents)   between  or  among  Restricted   Subsidiaries   (excluding
Subsidiaries  described in clause (b) of the definition of  "Subsidiary") of the
Borrower,   (ii)  the  disposition  of  communications   tower  facilities  that
contribute  in the  aggregate,  less than (A) five percent (5%) of the Operating
Cash Flow of Borrower for the twelve calendar month period immediately preceding
such  disposition,  and (B) fifteen  percent (15%) of the Operating Cash Flow of
the  Borrower  for the period from the  Agreement  Date through the date of such
disposition or (iii) subject to Section 2.5(c) hereof,  any other property (real
or personal) not used or useful in Borrower's  or such  Restricted  Subsidiary's
business.  Upon any sale or  disposition  of a Restricted  Subsidiary  permitted
hereunder,  the Administrative Agent and the Banks shall, at Borrower's expense,
take such actions as the Borrower  reasonably  requests to cause such Restricted
Subsidiary to be released from its obligations under the Subsidiary Guaranty.

                  (b)  Liquidation or Merger.  The Borrower shall not, and shall
not permit  any of its  Restricted  Subsidiaries  to, at any time  liquidate  or
dissolve itself (or suffer any liquidation or dissolution) or otherwise wind up,
or enter into any  merger,  other than (i) a merger or  consolidation  among the
Borrower and one or more Restricted  Subsidiaries,  provided the Borrower is the
surviving corporation,  or (ii) a merger between or among two or more Restricted
Subsidiaries,  or (iii) in connection  with an Acquisition  permitted  hereunder
effected by a merger in which the Borrower or, in a merger in which the Borrower
is not a party,  a Restricted  Subsidiary  is the surviving  corporation  or the
surviving corporation becomes a Restricted Subsidiary.

         Section 7.5 Limitation on Guaranties. The Borrower shall not, and shall
not permit any of its Restricted Subsidiaries to, at any time Guaranty,  assume,
be obligated with respect to, or permit to be  outstanding  any Guaranty of, any
obligation  of any other  Person  other than (a) a guaranty  by  endorsement  of
negotiable instruments for collection in the ordinary course of business, or (b)
obligations   under  agreements  of  the  Borrower  or  any  of  its  Restricted
Subsidiaries entered into in connection


                                      -58-


<PAGE>



with Acquisitions  permitted under this Agreement leases of real property or the
acquisition  of  services,  supplies and  equipment  in the  ordinary  course of
business  of  the  Borrower  or  any  of  its  Restricted  Subsidiaries,  or (c)
Guaranties of Indebtedness incurred as permitted pursuant to Section 7.1 hereof,
or (d) as may be contained in any Loan Document  including,  without limitation,
any Subsidiary Guaranty.

         Section 7.6 Investments and  Acquisitions.  The Borrower shall not, and
shall not permit any of its Restricted  Subsidiaries  to, directly or indirectly
make any loan or advance,  or otherwise acquire for  consideration  evidences of
Indebtedness, capital stock or other securities of any Person or other assets or
property (other than assets or property in the ordinary course of business),  or
make any Acquisition,  except that so long as no Default then exists or would be
caused thereby:

                  (a) The Borrower and its Restricted Subsidiaries may, directly
or through a brokerage account (i) purchase  marketable,  direct  obligations of
the United States of America, its agencies and instrumentalities maturing within
three  hundred  sixty-five  (365) days of the date of  purchase,  (ii)  purchase
commercial  paper,  money-market  funds and business  savings accounts issued by
corporations,  each of which  shall have a  combined  net worth of at least $100
million and each of which  conducts a  substantial  part of its  business in the
United States of America,  maturing  within two hundred  seventy (270) days from
the date of the  original  issue  thereof,  and rated "P-2" or better by Moody's
Investors Service, Inc. or "A-2" or better by Standard and Poor's Ratings Group,
a division  of  McGraw-Hill,  (iii)  purchase  repurchase  agreements,  bankers'
acceptances, and domestic and Eurodollar certificates of deposit maturing within
three hundred sixty-five (365) days of the date of purchase which are issued by,
or time deposits  maintained  with, a United  States  national or state bank the
deposits of which are insured by the Federal  Deposit  Insurance  Corporation or
the Federal Savings and Loan Insurance  Corporation and having capital,  surplus
and undivided profits totaling more than $100 million and rated "A" or better by
Moody's Investors Service, Inc. or Standard and Poor's Ratings Group, a division
of McGraw-Hill, Inc.; and

                  (b)  Subject to  compliance  with  Section  5.14  hereof,  the
Borrower or any of its Restricted  Subsidiaries may (i) make Acquisitions;  (ii)
initiate  construction of new  communications  tower facilities;  and (iii) make
investments in  Unrestricted  Subsidiaries  so long as the maximum amount of the
proceeds  of the  Loans  invested  or  used to  acquire  interests  in any  such
Unrestricted  Subsidiary  does  not  exceed  the sum of (A)  $13,500,000  in the
aggregate  during the term hereof and (B) to the extent not used for  Restricted
Payments,  funds  permitted  to be used  for  Restricted  Payments  pursuant  to
Sections 7.7(a) and


                                      -59-


<PAGE>



(b) hereof,  provided that proceeds from the  disposition of any such investment
permitted by this clause (b)(iii),  shall be available to be used for Restricted
Payments or to make additional  investments  permitted hereunder;  provided that
Borrower  may,  subject to Section  2.5(d)  hereof,  use the Net Proceeds of any
issuance of equity interests to invest in any such Unrestricted  Subsidiary over
and above the limitations set forth in this clause (b).

         Section 7.7  Restricted  Payments The Borrower shall not, and shall not
permit any of its Restricted  Subsidiaries to, directly or indirectly declare or
make any  Restricted  Payment;  provided,  however,  that so long as no  Default
hereunder  then exists or would be caused  thereby,  the  Borrower  may make (a)
subject to Section 2.5(b) hereof,  cash distributions in an amount not to exceed
(i) fifty  percent  (50%) of  Excess  Cash  Flow for the  immediately  preceding
calendar  year, on or after April 15 of each  calendar year  commencing on April
15,  2000 less (ii) any  portion  thereof  used for  purposes  of  investing  in
Unrestricted  Subsidiaries;  (b) cash distributions from (i) fifty percent (50%)
of the net proceeds of any equity  offering  less (ii) any portion  thereof used
for  purposes of  investing  in  Unrestricted  Subsidiaries,  subject to Section
2.5(d) hereof and so long as the Leverage Ratio on such date is less than 4.0 to
1 after giving effect to any payment pursuant to Section  2.7(b)(iv)  hereof and
(c) a $500,000 cash  distribution to Parent or American Radio Systems out of the
Net Proceeds of the Philadelphia Disposition.

         Section 7.8 Leverage Ratio. (a) As of the end of any calendar  quarter,
and (b) at the  time of any  Advance  hereunder  (after  giving  effect  to such
Advance),  the Borrower shall not permit its Leverage Ratio to exceed the ratios
set forth below during the periods indicated:


    Period                                             Ratio

Agreement Date through                                 6.00:1
September 29, 1998

September 30, 1998 through                             5.50:1
March 30, 1999

March 31, 1999 through                                 5.00:1
September 29, 1999

September 30, 1999 through                             4.50:1
March 30, 2000

March 31, 2000 through                                 4.00:1
December 30, 2000



                                      -60-


<PAGE>





December 31, 2000 through                              3.50:1
December 30, 2001

December 31, 2001 and                                  3.00:1
thereafter


         Section 7.9 Interest  Coverage Ratio. The Borrower and its consolidated
Restricted  Subsidiaries shall maintain,  on a consolidated  basis, at all times
during the applicable  periods set forth below,  an Interest  Coverage Ratio for
such  fiscal  quarter of not less than the ratio set forth below  opposite  each
such period:

         Period                                        Ratio

         Agreement Date through                        2.00:1
         September 29, 1999

         September 30, 1999 and thereafter             2.50:1

         Section 7.10 Annualized  Operating Cash Flow to Pro Forma Debt Service.
(a) As of the end of any  calendar  quarter,  and (b) at the time of any Advance
hereunder  (after giving effect to such Advance),  the Borrower shall not permit
the  ratio  of  (i)  its  Annualized  Operating  Cash  Flow  (for  the  calendar
quarter/month end being tested in the case of Section 7.10(a) hereof, or for the
most  recently  completed  calendar  quarter/month  end,  in the case of Section
7.10(b) hereof) to (ii) its Pro Forma Debt Service to be less than the ratio set
forth below opposite each such period:

                  Period                               Ratio

         Agreement Date through                        1.10:1
         September 29, 1999

         September 30, 1999 and                        1.15:1
         thereafter

         Section 7.11  Limitation on Capital  Expenditures.  The Borrower,  on a
consolidated basis with its Restricted


                                      -61-


<PAGE>



Subsidiaries,  shall not permit its Capital  Expenditures  to exceed the amounts
set forth below for the periods indicated:


                     Period                            Dollar Amount

Agreement Date through                                  $10,000,000
December 31, 1996

From January 1, 1997                                    $15,000,000
through December 31, 1997

From January 1, 1998                                     $8,000,000
through December 31, 1998

From January 1, 1999                                     $4,000,000
through December 31, 1999
and each calendar year
period thereafter


To the extent not used in any  calendar  year,  an amount equal to the lesser of
(a) the unused amounts permitted for Capital Expenditures for such calendar year
and (b) 15% of the maximum Capital  Expenditure  availability  for such calendar
year may (exclusive of any carryforwards  from prior periods) be carried forward
to the  next  calendar  year,  and may be  spent in  addition  to the  otherwise
applicable limitations for such year.

         Section 7.12 Affiliate  Transactions.  Except as specifically  provided
herein (including,  without limitation,  Sections 7.4 and 7.7 hereof) and as may
be described on Schedule  4.1(s)  attached  hereto,  the Borrower shall not, and
shall not permit any of its  Restricted  Subsidiaries  to, at any time engage in
any  transaction  with an Affiliate,  or make an assignment or other transfer of
any of its properties or assets to any Affiliate,  on terms less advantageous to
the  Borrower  or such  Restricted  Subsidiary  than  would  be the case if such
transaction had been effected with a non-Affiliate.

         Section 7.13 Real Estate.  Subject to Section 5.11 hereof, the Borrower
and its Restricted  Subsidiaries  may purchase real estate solely for use in the
business of the Borrower and its Restricted Subsidiaries unless incidental to an
Acquisition permitted hereunder.

         Section 7.14 ERISA Liabilities. The Borrower shall not, and shall cause
each of its ERISA  Affiliates  not to,  (i)  permit  the  assets of any of their
respective  Plans to be less than the amount  necessary  to provide  all accrued
benefits under such Plans, or (ii) enter into any Multiemployer Plan.




                                      -62-


<PAGE>



                                    ARTICLE 8

                                     Default

         Section 8.1 Events of Default.  Each of the following shall  constitute
an Event of Default,  whatever the reason for such event and whether it shall be
voluntary or  involuntary  or be effected by operation of law or pursuant to any
judgment  or  order  of any  court  or any  order,  rule  or  regulation  of any
governmental or non-governmental body:

                  (a) Any  representation  or warranty made under this Agreement
shall prove incorrect or misleading in any material  respect when made or deemed
to be made pursuant to Section 4.2 hereof;

                  (b) The  Borrower  shall  default in the  payment  of: (i) any
interest  under any of the Notes or fees or other  amounts  payable to the Banks
and the  Administrative  Agent under any of the Loan Documents,  or any of them,
when due,  and such  Default  shall not be cured by payment in full within three
(3)  Business  Days from the due date;  or (ii) any  principal  under any of the
Notes when due;

                  (c) The  Borrower  shall  default  (i) in the  performance  or
observance  of any  agreement or covenant  contained in Sections  5.2(a) or 5.10
hereof, or Sections 7.1, 7.2, 7.4, 7.5, 7.7, 7.8, 7.9, 7.10 and 7.11 hereof;

                  (d)  The  Borrower   shall  default  in  the   performance  or
observance of any other  agreement or covenant  contained in this  Agreement not
specifically  referred to elsewhere in this Section 8.1, and such default  shall
not be cured  within a period of thirty  (30) days (or with  respect to Sections
5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 5.14,  5.15,  5.16, 6.4, 6.5, 7.3, 7.12, 7.13
and 7.14,  such longer  period not to exceed  sixty (60) days if such default is
curable within such period and the Borrower is proceeding in good faith with all
diligent  efforts to cure such default) from the later of (i) occurrence of such
Default and (ii) the date on which such Default became known to the Borrower;

                  (e)  There  shall  occur any  default  in the  performance  or
observance  of any  agreement  or  covenant or breach of any  representation  or
warranty contained in any of the Loan Documents (other than this Agreement or as
otherwise provided in Section 8.1 of this Agreement) by the Borrower, any of its
Restricted  Subsidiaries,  or any other obligor  thereunder,  which shall not be
cured  within a period of thirty (30) days (or such longer  period not to exceed
sixty (60) days if such  default is cured within such period and the Borrower is
proceeding  in good faith with all diligent  efforts to cure such  default) from
the


                                      -63-


<PAGE>



later of (i) occurrence of such Default and (ii) date on which
such default became known to the Borrower;

                  (f) There  shall be entered  and  remain  unstayed a decree or
order for relief in respect of the Borrower or any of the Borrower's  Restricted
Subsidiaries  under Title 11 of the United  States Code, as now  constituted  or
hereafter  amended,  or any other applicable  Federal or state bankruptcy law or
other  similar law, or  appointing a receiver,  liquidator,  assignee,  trustee,
custodian,  sequestrator  or  similar  official  of the  Borrower  or any of the
Borrower's  Restricted  Subsidiaries,  or  of  any  substantial  part  of  their
respective properties,  or ordering the winding-up or liquidation of the affairs
of  the  Borrower,  or  any of the  Borrower's  Restricted  Subsidiaries;  or an
involuntary  petition  shall  be  filed  against  the  Borrower  or  any  of the
Borrower's  Restricted  Subsidiaries and a temporary stay entered,  and (i) such
petition and stay shall not be diligently  contested,  or (ii) any such petition
and stay shall  continue  undismissed  for a period of ninety  (90)  consecutive
days;

                  (g)  The  Borrower  or  any  of  the   Borrower's   Restricted
Subsidiaries shall file a petition, answer or consent seeking relief under Title
11 of the United States Code, as now  constituted or hereafter  amended,  or any
other  applicable  Federal or state  bankruptcy law or other similar law, or the
Borrower or any of the Borrower's  Restricted  Subsidiaries shall consent to the
institution of  proceedings  thereunder or to the filing of any such petition or
to the appointment or taking of possession of a receiver, liquidator,  assignee,
trustee,  custodian,  sequestrator or other similar  official of the Borrower or
any of the Borrower's  Restricted  Subsidiaries  or of any  substantial  part of
their respective properties, or the Borrower or any of the Borrower's Restricted
Subsidiaries  shall fail generally to pay their  respective debts as they become
due or shall be adjudicated insolvent; the Borrower shall suspend or discontinue
its  business;  the Borrower or any of the  Borrower's  Restricted  Subsidiaries
shall have  concealed,  removed any of its property with the intent to hinder or
defraud its creditors or shall have made a fraudulent or  preferential  transfer
under any applicable fraudulent conveyance or bankruptcy law, or the Borrower or
any  of  the  Borrower's  Restricted  Subsidiaries  shall  take  any  action  in
furtherance of any such action;

                  (h) A judgment not covered by  insurance  or  indemnification,
where the indemnifying  party has agreed to indemnify and is financially able to
do so,  shall  be  entered  by any  court  against  the  Borrower  or any of the
Borrower's Restricted Subsidiaries for the payment of money which exceeds singly
or in the  aggregate  with other  such  judgments,  $1,000,000,  or a warrant of
attachment  or execution or similar  process  shall be issued or levied  against
property of the Borrower or any of


                                      -64-


<PAGE>



the  Borrower's  Restricted  Subsidiaries  which,  together  with all other such
property  of the  Borrower  or any of  the  Borrower's  Restricted  Subsidiaries
subject to other such process, exceeds in value $1,000,000 in the aggregate, and
if,  within  thirty  (30) days  after the  entry,  issue or levy  thereof,  such
judgment,  warrant or process  shall not have been paid or  discharged or stayed
pending appeal or removed to bond, or if, after the expiration of any such stay,
such  judgment,  warrant or process  shall not have been paid or  discharged  or
removed to bond;

                  (i)  There  shall  be at any  time  any  "accumulated  funding
deficiency,"  as defined in ERISA or in Section 412 of the Code, with respect to
any Plan  maintained  by the  Borrower or any of its  Subsidiaries  or any ERISA
Affiliate,  or to which the  Borrower  or any of its  Subsidiaries  or any ERISA
Affiliate has any  liabilities,  or any trust created  thereunder;  or a trustee
shall be appointed by a United  States  District  Court to  administer  any such
Plan;  or PBGC shall  institute  proceedings  to terminate any such Plan; or the
Borrower  or any of its  Subsidiaries  or any ERISA  Affiliate  shall  incur any
liability to PBGC in connection  with the  termination  of any such Plan; or any
Plan or trust created under any Plan of the Borrower or any of its  Subsidiaries
or any ERISA Affiliate shall engage in a "prohibited  transaction" (as such term
is defined in Section  406 of ERISA or  Section  4975 of the Code)  which  would
subject  any  such  Plan,   any  trust  created   thereunder,   any  trustee  or
administrator  thereof,  or any party dealing with any such Plan or trust to the
tax or penalty on "prohibited  transactions"  imposed by Section 502 of ERISA or
Section 4975 of the Code;

                  (j) There shall occur (i) any  acceleration of the maturity of
any   Indebtedness  of  the  Borrower  or  any  of  the  Borrower's   Restricted
Subsidiaries in an aggregate  principal  amount exceeding  $1,000,000,  or, as a
result of a failure to comply with the terms thereof,  such  Indebtedness  shall
otherwise  have  become  due and  payable;  (ii)  any  event  or  condition  the
occurrence  of which would permit such  acceleration  of such  Indebtedness,  or
which,  as a result of a failure to comply  with the terms  thereof,  would make
such  Indebtedness  otherwise due and payable,  and which event or condition has
not been cured within any  applicable  cure period or waived in writing prior to
any declaration of an Event of Default or  acceleration of the Loans  hereunder;
or (iii) any material  default under any Interest  Hedge  Agreement  which would
permit the  obligation  of the  Borrower to make  payments  to the  counterparty
thereunder to be then due and payable;

                  (k) The Borrower and its Restricted  Subsidiaries  are for any
reason no longer  able to  operate or manage the  related  communications  tower
facilities or portions  thereof and retain the revenue received  therefrom,  and
the overall effect of such


                                      -65-


<PAGE>



loss,  destruction,  termination,  revocation  or failure  to renew  would be to
reduce  Operating Cash Flow  (determined as at the last day of the most recently
ended fiscal year of the Borrower) by ten percent (10%) or more;

                  (l) Any  material  Loan  Document  or any  material  provision
thereof,  shall  at any  time  and for any  reason  be  declared  by a court  of
competent  jurisdiction to be null and void, or a proceeding  shall be commenced
by the  Borrower  or any of the  Borrower's  Restricted  Subsidiaries  or by any
governmental  authority  having  jurisdiction  over the  Borrower  or any of the
Borrower's  Restricted  Subsidiaries  seeking to  establish  the  invalidity  or
unenforceability  thereof  (exclusive  of  questions  of  interpretation  of any
provision thereof), or the Borrower or any of the Borrower's  Subsidiaries shall
deny that it has any  liability  or  obligation  for the payment of principal or
interest purported to be created under any Loan Document;

                  (m) Any material Security Document shall for any reason,  fail
or cease (except by reason of lapse of time) to create a valid and perfected and
first-priority  Lien on or  Security  Interest  in any  material  portion of the
Collateral purported to be covered thereby;

                  (n)      There shall occur any Change of Control; or

                  (o)      Borrower or any of its Restricted Subsidiaries
shall be indicted under the Racketeer Influenced and Corrupt
Organizations Act of 1970 (18 U.S.C. ss. 1961 et seq.).

         Section 8.2 Remedies.

                  (a) If an Event of Default  specified  in  Section  8.1 (other
than an Event of Default  under  Section  8.1(f) or Section  8.1(g))  shall have
occurred and shall be continuing,  the  Administrative  Agent, at the request of
the Majority  Banks subject to Section  9.8(a)  hereof,  shall (i) terminate the
Commitment,  and/or (ii) declare the  principal of and interest on the Loans and
the Notes and all other amounts owed to the Banks and the  Administrative  Agent
under this Agreement, the Notes and any other Loan Documents to be forthwith due
and payable without  presentment,  demand,  protest or other notice of any kind,
all of which are hereby expressly waived, anything in this Agreement,  the Notes
or any other Loan Document to the contrary  notwithstanding,  and the Commitment
shall thereupon forthwith terminate.

                  (b) Upon the occurrence and continuance of an Event of Default
specified in Section 8.1(f) or Section 8.1(g), all principal, interest and other
amounts due  hereunder  and under the Notes,  and all other  Obligations,  shall
thereupon and


                                      -66-


<PAGE>



concurrently therewith become due and payable and the Commitment shall forthwith
terminate and the principal amount of the Loans outstanding hereunder shall bear
interest at the Default Rate, all without any action by the Administrative Agent
or the  Banks or the  Majority  Banks or any of them  and  without  presentment,
demand,  protest or other notice of any kind, all of which are expressly waived,
anything  in this  Agreement  or in the other  Loan  Documents  to the  contrary
notwithstanding.

                  (c) Upon  acceleration of the Notes, as provided in subsection
(a) or (b) of this Section 8.2, above,  the  Administrative  Agent and the Banks
shall have all of the  post-default  rights  granted to them, or any of them, as
applicable under the Loan Documents and under Applicable Law.

                  (d) Upon  acceleration of the Notes, as provided in subsection
(a) or (b) of this Section 8.2,  the  Administrative  Agent shall have the right
(but  not  the  obligation)  upon  the  request  of the  Banks  to  operate  the
communications tower facilities of the Borrower and its Restricted  Subsidiaries
in  accordance  with the terms of the  Licenses  and  pursuant  to the terms and
subject to any  limitations  contained in the  Security  Documents  and,  within
guidelines  established by the Majority  Banks, to make any and all payments and
expenditures necessary or desirable in connection therewith,  including, without
limitation,  payment of wages as required under the Fair Labor Standards Act, as
amended, and of any necessary withholding taxes to state or federal authorities.
In the event the Majority Banks fail to agree upon the guidelines referred to in
the preceding  sentence  within six (6) Business Days' after the  Administrative
Agent  has  begun  to  operate  the   communications   tower   facilities,   the
Administrative  Agent may,  after giving three (3) days' prior written notice to
the Banks of its intention to do so, make such payments and  expenditures  as it
deems  reasonable  and  advisable in its sole  discretion to maintain the normal
day-to-day operation of such communications tower facilities.  Such payments and
expenditures  in  excess  of  receipts  shall  constitute   Advances  under  the
Commitment,  not in  excess  of the  amount  of the  Commitment.  Advances  made
pursuant  to this  Section  8.2(d)  shall bear  interest  as provided in Section
2.3(d) and shall be payable on demand.  The making of one or more Advances under
this Section  8.2(d) shall not create any obligation on the part of the Banks to
make any additional Advances hereunder.  No exercise by the Administrative Agent
of the rights granted to it under this Section 8.2(d) shall  constitute a waiver
of any other rights and  remedies  granted to the  Administrative  Agent and the
Banks,  or any of them,  under this  Agreement or at law.  The  Borrower  hereby
irrevocably  appoints the Administrative  Agent as agent for the Banks, the true
and lawful attorney of the Borrower, in its name and stead and on its behalf, to
execute,  receipt for or otherwise act in connection with any and all contracts,
instruments or


                                      -67-


<PAGE>



other  documents  in  connection  with  the  completion  and  operation  of  the
communications  tower facilities in the exercise of the  Administrative  Agent's
and the Banks'  rights  under this  Section  8.2(d).  Such power of  attorney is
coupled with an interest and is  irrevocable.  The rights of the  Administrative
Agent under this Section  8.2(d) shall be subject to its prior  compliance  with
the Communications Act and the FCC rules and policies promulgated  thereunder to
the extent applicable to the exercise of such rights.

                  (e) Upon  acceleration of the Notes, as provided in subsection
(a) or (b) of this Section 8.2, the  Administrative  Agent,  upon request of the
Majority  Banks,  shall have the right to the  appointment of a receiver for the
properties and assets of the Borrower and its Restricted  Subsidiaries,  and the
Borrower,  for  itself  and on behalf  of its  Restricted  Subsidiaries,  hereby
consents to such rights and such appointment and hereby waives any objection the
Borrower or any  Restricted  Subsidiary  may have thereto or the right to have a
bond or other  security  posted  by the  Administrative  Agent on  behalf of the
Banks, in connection  therewith.  The rights of the  Administrative  Agent under
this  Section  8.2(e)  shall  be  subject  to  its  prior  compliance  with  the
Communications Act and the FCC rules and policies promulgated  thereunder to the
extent applicable to the exercise of such rights.

                  (f)      The rights and remedies of the Administrative
Agent and the Banks hereunder shall be cumulative, and not
exclusive.

         Section 8.3 Payments  Subsequent  to  Declaration  of Event of Default.
Subsequent to the  acceleration of the Loans under Section 8.2 hereof,  payments
and prepayments  under this Agreement made to the  Administrative  Agent and the
Banks  or  otherwise  received  by any of  such  Persons  (from  realization  on
Collateral  for  the  Obligations  or  otherwise)  shall  be  paid  over  to the
Administrative  Agent (if necessary) and distributed by the Administrative Agent
as follows:  first, to the Administrative Agent's reasonable costs and expenses,
if  any,  incurred  in  connection  with  the  collection  of  such  payment  or
prepayment,  including,  without limitation, any reasonable costs incurred by it
in connection with the sale or disposition of any Collateral for the Obligations
and all  amounts  under  Section  11.2(b) and (c);  second,  to the Banks or the
Administrative  Agent for any fees  hereunder  or under  any of the  other  Loan
Documents  then due and  payable;  third,  to the Banks pro rata on the basis of
their  respective  unpaid  principal  amounts  (except  as  provided  in Section
2.2(e)),  to the payment of any unpaid  interest  which may have  accrued on the
Obligations;  fourth,  to the Banks pro rata  until all Loans  have been paid in
full (and,  for  purposes  of this  clause,  obligations  under  Interest  Hedge
Agreements with the


                                      -68-


<PAGE>



Banks or any of them shall be paid on a pro rata basis with the  Loans);  fifth,
to the Banks pro rata on the basis of their  respective  unpaid amounts,  to the
payment of any other  unpaid  Obligations;  and  sixth,  to the  Borrower  or as
otherwise required by law.


                                    ARTICLE 9

                            The Administrative Agent

         Section 9.1 Appointment and Authorization. Each Bank hereby irrevocably
appoints and  authorizes,  and hereby agrees that it will require any transferee
of any of its  interest in its portion of the Loans and in its Note  irrevocably
to appoint and authorize,  the Administrative  Agent to take such actions as its
agent on its behalf and to exercise  such powers  hereunder  and under the other
Loan  Documents as are delegated by the terms hereof and thereof,  together with
such powers as are reasonably  incidental  thereto.  Neither the  Administrative
Agent, nor any of its respective directors, officers, employees or agents, shall
be liable for any action taken or omitted to be taken by it or them hereunder or
in connection herewith,  except for its or their own gross negligence or willful
misconduct as determined by a final, non-appealable judicial order of a court of
competent jurisdiction.

         Section 9.2 Interest Holders.  The Administrative  Agent may treat each
Bank, or the Person designated in the last notice filed with the  Administrative
Agent,  as the holder of all of the interests of such Bank in its portion of the
Loans and in its Note until written notice of transfer,  signed by such Bank (or
the Person  designated in the last notice filed with the  Administrative  Agent)
and by the Person  designated  in such written  notice of transfer,  in form and
substance  satisfactory to the Administrative  Agent, shall have been filed with
the Administrative Agent.

         Section 9.3 Consultation  with Counsel.  The  Administrative  Agent may
consult with  Powell,  Goldstein,  Frazer & Murphy,  Atlanta,  Georgia,  special
counsel to the Administrative  Agent, or with other legal counsel selected by it
and shall not be liable for any action  taken or suffered by it in good faith in
consultation  with  the  Majority  Banks  and in  reasonable  reliance  on  such
consultations.

         Section 9.4 Documents.  The Administrative Agent shall be under no duty
to  examine,  inquire  into,  or  pass  upon  the  validity,   effectiveness  or
genuineness  of this  Agreement,  any Note,  any  other  Loan  Document,  or any
instrument, document or communication furnished pursuant hereto or in connection


                                      -69-


<PAGE>



herewith, and the Administrative Agent shall be entitled to assume that they are
valid, effective and genuine, have been signed or sent by the proper parties and
are what they purport to be.

         Section 9.5  Administrative  Agent and Affiliates.  With respect to the
Commitment and the Loans,  the  Administrative  Agent shall have the same rights
and  powers  hereunder  as any  other  Bank  and the  Administrative  Agent  and
Affiliates of the  Administrative  Agent may accept deposits from, lend money to
and  generally  engage in any kind of  business  with the  Borrower,  any of its
Subsidiaries or any Affiliates of, or Persons doing business with, the Borrower,
as if they were not  affiliated  with the  Administrative  Agent and without any
obligation to account therefor.

         Section 9.6 Responsibility of the Administrative  Agent. The duties and
obligations  of the  Administrative  Agent under this  Agreement  are only those
expressly  set  forth  in this  Agreement.  The  Administrative  Agent  shall be
entitled  to assume  that no  Default or Event of Default  has  occurred  and is
continuing  unless it has actual  knowledge,  or has been notified in writing by
the Borrower,  of such fact, or has been notified by a Bank in writing that such
Bank  considers  that a  Default  or an Event of  Default  has  occurred  and is
continuing, and such Bank shall specify in detail the nature thereof in writing.
The  Administrative  Agent shall not be liable hereunder for any action taken or
omitted to be taken except for its own gross negligence or willful misconduct as
determined  by a final,  non-appealable  judicial  order of a court of competent
jurisdiction.  The  Administrative  Agent shall provide each Bank with copies of
such documents received from the Borrower as such Bank may reasonably request.

         Section 9.7 Action by the Administrative Agent.

                  (a) The  Administrative  Agent  shall be  entitled  to use its
discretion  with respect to exercising or refraining  from exercising any rights
which may be vested in it by,  and with  respect  to taking or  refraining  from
taking any  action or  actions  which it may be able to take under or in respect
of, this Agreement,  unless the Administrative  Agent shall have been instructed
by the Majority Banks to exercise or refrain from  exercising  such rights or to
take or refrain from taking such action;  provided that the Administrative Agent
shall not exercise any rights under Section 8.2(a) of this Agreement without the
request of the Majority  Banks (or,  where  expressly  required,  all the Banks)
unless time is of the  essence,  in which case,  such action can be taken at the
request of the  Administrative  Agent. The  Administrative  Agent shall incur no
liability  under or in respect of this  Agreement with respect to anything which
it may do or refrain from doing in the reasonable exercise of its


                                      -70-


<PAGE>



judgment  or  which  may  seem  to  it to  be  necessary  or  desirable  in  the
circumstances,  except  for  its  gross  negligence  or  willful  misconduct  as
determined  by  a  final,  non-appealable  judicial  order  of  a  court  having
jurisdiction over the subject matter.

                  (b) The Administrative  Agent shall not be liable to the Banks
or to any Bank or the Borrower or any of the Borrower's  Subsidiaries  in acting
or  refraining  from acting under this  Agreement or any other Loan  Document in
accordance  with the  instructions  of the Majority Banks (or,  where  expressly
required,  all the Banks),  and any action  taken or failure to act  pursuant to
such instructions shall be binding on all Banks, except for its gross negligence
or willful misconduct as determined by a final, non-appealable judicial order of
a court having  jurisdiction over the subject matter. The  Administrative  Agent
shall not be  obligated  to take any action  which is  contrary  to law or which
would in its reasonable opinion subject it to liability.

         Section  9.8 Notice of Default or Event of  Default.  In the event that
the  Administrative  Agent or any Bank shall acquire actual knowledge,  or shall
have been notified, of any Default or Event of Default, the Administrative Agent
or such Bank  shall  promptly  notify the Banks  (provided  failure to give such
notice  shall  not  result  in any  liability  on  the  part  of  such  Bank  or
Administrative  Agent), and the Administrative  Agent shall take such action and
assert such rights  under this  Agreement  and the other Loan  Documents  as the
Majority Banks shall request in writing,  and the Administrative Agent shall not
be  subject  to any  liability  by reason  of its  acting  pursuant  to any such
request. If the Majority Banks shall fail to request the Administrative Agent to
take action or to assert rights under this Agreement or any other Loan Documents
in respect of any  Default or Event of Default  within ten (10) days after their
receipt of the notice of any Default or Event of Default from the Administrative
Agent or any Bank,  or shall  request  inconsistent  action with respect to such
Default or Event of  Default,  the  Administrative  Agent may,  but shall not be
required  to, take such action and assert such rights  (other than rights  under
Article  8  hereof)  as it  deems  in its  discretion  to be  advisable  for the
protection of the Banks,  except that, if the Majority Banks have instructed the
Administrative  Agent not to take such action or assert such right,  in no event
shall the Administrative  Agent act contrary to such instructions unless time is
of the essence,  in which case, the  Administrative  Agent may act in accordance
with its reasonable discretion.



                                      -71-


<PAGE>



         Section 9.9 Responsibility  Disclaimed.  The Administrative Agent shall
not be under any liability or responsibility whatsoever as Administrative Agent:

                  (a)      To the Borrower or any other Person as a
consequence of any failure or delay in performance by or any
breach by, any Bank or Banks of any of its or their obligations
under this Agreement;

                  (b) To any Bank or Banks,  as a consequence  of any failure or
delay in  performance  by, or any  breach  by,  (i) the  Borrower  of any of its
obligations  under this  Agreement or the Notes or any other Loan  Document,  or
(ii) any  Restricted  Subsidiary  of the Borrower or any other obligor under any
other Loan Document;

                  (c) To any Bank or Banks, for any statements,  representations
or warranties in this  Agreement,  or any other  document  contemplated  by this
Agreement or any information provided pursuant to this Agreement, any other Loan
Document,  or any other  document  contemplated  by this  Agreement,  or for the
validity,  effectiveness,  enforceability or sufficiency of this Agreement,  the
Notes,  any other Loan  Document,  or any other  document  contemplated  by this
Agreement; or

                  (d) To any  Person  for any act or  omission  other  than that
arising from gross negligence or willful misconduct of the Administrative  Agent
as determined by a final,  non-appealable judicial order of a court of competent
jurisdiction.

         Section  9.10  Indemnification.   The  Banks  agree  to  indemnify  the
Administrative  Agent (to the extent not  reimbursed  by the  Borrower) pro rata
according to their respective  Commitment  Ratios,  from and against any and all
liabilities,  obligations, losses (other than the loss of principal and interest
hereunder in the event of a bankruptcy or out-of-court `work-out' of the Loans),
damages,  penalties,  actions, judgments, suits, costs, expenses (including fees
and expenses of experts,  agents,  consultants and counsel), or disbursements of
any kind or nature  whatsoever  which may be imposed on, incurred by or asserted
against the  Administrative  Agent in any way relating to or arising out of this
Agreement,  any other Loan Document,  or any other document contemplated by this
Agreement  or any other  Loan  Document  or any  action  taken or omitted by the
Administrative Agent under this Agreement, any other Loan Document, or any other
document contemplated by this Agreement,  except that no Bank shall be liable to
the  Administrative  Agent for any  portion  of such  liabilities,  obligations,
losses,  damages,  penalties,  actions,  judgments,  suits, costs,  expenses, or
disbursements  resulting from the gross negligence or willful  misconduct of the
Administrative Agent as determined by a final, non-appealable


                                      -72-


<PAGE>



judicial order of a court having jurisdiction over the subject
matter.

         Section 9.11 Credit Decision. Each Bank represents and warrants to each
other and to the Administrative Agent that:

                  (a) In making its decision to enter into this Agreement and to
make its  portion  of the Loans it has  independently  taken  whatever  steps it
considers  necessary  to evaluate  the  financial  condition  and affairs of the
Borrower and that it has made an independent  credit  judgment,  and that it has
not  relied  upon  the  Administrative  Agent  or  information  provided  by the
Administrative  Agent  (other than  information  provided to the  Administrative
Agent by the Borrower and forwarded by the  Administrative  Agent to the Banks);
and

                  (b) So long as any portion of the Loans remains outstanding or
such Bank has an obligation to make its portion of Advances  hereunder,  it will
continue to make its own independent  evaluation of the financial  condition and
affairs of the Borrower.

         Section 9.12 Successor Administrative Agent. Subject to the appointment
and  acceptance  of a  successor  Administrative  Agent as provided  below,  the
Administrative  Agent may resign at any time by giving written notice thereof to
the  Banks  and the  Borrower  and may be  removed  at any time for cause by the
Majority Banks.  Upon any such resignation or removal,  the Majority Banks shall
have the right to appoint a successor  Administrative  Agent  which  appointment
shall,  prior to a Default,  be subject to the consent of the  Borrower,  acting
reasonably.  If (a)  no  successor  Administrative  Agent  shall  have  been  so
appointed by the Majority Banks or (b) if appointed, no successor Administrative
Agent shall have  accepted  such  appointment  within thirty (30) days after the
retiring  Administrative  Agent gave notice of resignation or the Majority Banks
removed the retiring  Administrative  Agent,  then the  retiring  Administrative
Agent may,  on behalf of the Banks,  appoint a  successor  Administrative  Agent
which shall be any Bank or a  commercial  bank  organized  under the laws of the
United States of America or any political subdivision thereof which has combined
capital and  reserves in excess of  $250,000,000  and which shall be  reasonably
acceptable  to  the  Borrower.   Upon  the  acceptance  of  any  appointment  as
Administrative  Agent  hereunder  by  a  successor   Administrative  Agent  such
successor Administrative Agent shall thereupon succeed to and become vested with
all the rights,  powers,  privileges,  duties and  obligations  of the  retiring
Administrative  Agent and the retiring  Administrative Agent shall be discharged
from its duties and  obligations  hereunder and under the other Loan  Documents.
After any retiring  Administrative  Agent's  resignation or removal hereunder as
Administrative Agent the provisions of


                                      -73-


<PAGE>



this Article shall  continue in effect for its benefit in respect of any actions
taken or  omitted  to be taken by it while it was  acting as the  Administrative
Agent.  In the  event  that the  Administrative  Agent or any of its  respective
affiliates  ceases to be a Bank  hereunder,  such Person shall resign its agency
hereunder.

         Section 9.13 Delegation of Duties. The Administrative Agent may execute
any of its duties  under the Loan  Documents  by or through  agents or attorneys
selected by it using reasonable care, and shall be entitled to advice of counsel
concerning all matters pertaining to such duties.


                                   ARTICLE 10

                             Change in Circumstances
                            Affecting LIBOR Advances

         Section 10.1 LIBOR Basis  Determination  Inadequate or Unfair.  If with
respect  to  any  proposed   LIBOR   Advance  for  any  Interest   Period,   the
Administrative  Agent determines after consultation with the Banks that deposits
in dollars (in the applicable amount) are not being offered to each of the Banks
in the relevant market for such Interest Period, the Administrative  Agent shall
forthwith give notice thereof to the Borrower and the Banks, whereupon until the
Administrative Agent notifies the Borrower that the circumstances giving rise to
such situation no longer exist, the obligations of any affected Bank to make its
portion of such LIBOR Advances shall be suspended.

         Section 10.2 Illegality.  If after the date hereof, the adoption of any
Applicable  Law, or any change in any Applicable Law (whether  adopted before or
after the Agreement  Date), or any change in  interpretation  or  administration
thereof by any governmental authority, central bank or comparable agency charged
with the  interpretation  or administration  thereof,  or compliance by any Bank
with  any  directive  (whether  or not  having  the  force  of law) of any  such
authority,  central  bank  or  comparable  agency,  shall  make it  unlawful  or
impossible for any Bank to make, maintain or fund its portion of LIBOR Advances,
such Bank shall so notify the Administrative Agent, and the Administrative Agent
shall forthwith give notice thereof to the other Banks and the Borrower.  Before
giving any notice to the  Administrative  Agent  pursuant to this Section  10.2,
such Bank shall designate a different  lending office if such  designation  will
avoid the need for  giving  such  notice  and will not,  in the sole  reasonable
judgment of such Bank,  be otherwise  materially  disadvantageous  to such Bank.
Upon receipt of such  notice,  notwithstanding  anything  contained in Article 2
hereof,  the Borrower shall repay in full the then outstanding  principal amount
of such Bank's portion of


                                      -74-


<PAGE>



each affected LIBOR Advance,  together with accrued interest thereon,  on either
(a) the last day of the then current Interest Period applicable to such affected
LIBOR  Advances if such Bank may  lawfully  continue  to  maintain  and fund its
portion of such LIBOR  Advance to such day or (b)  immediately  if such Bank may
not lawfully  continue to fund and maintain its portion of such  affected  LIBOR
Advances to such day.  Concurrently  with repaying such portion of each affected
LIBOR  Advance,  the  Borrower  may borrow a Base Rate  Advance  from such Bank,
whether or not it would have been  entitled  to effect such  borrowing  and such
Bank  shall  make such  Advance,  if so  requested,  in an amount  such that the
outstanding  principal amount of the affected Note held by such Bank shall equal
the outstanding principal amount of such Note or Notes immediately prior to such
repayment.

         Section 10.3 Increased Costs.

                  (a) If after the date hereof,  the adoption of any  Applicable
Law, or any change in any  Applicable  Law (whether  adopted before or after the
Agreement  Date),  or  any   interpretation   or  change  in  interpretation  or
administration thereof by any governmental authority, central bank or comparable
agency charged with the  interpretation or administration  thereof or compliance
by any Bank with any  directive  (whether or not having the force of law) of any
such authority, central bank or comparable agency:

                           (1) shall  subject any Bank to any tax, duty or other
         charge  with  respect to its  obligation  to make its  portion of LIBOR
         Advances,  or its portion of  existing  Advances,  or shall  change the
         basis  of  taxation  of  payments  to any Bank of the  principal  of or
         interest  on its  portion of LIBOR  Advances or in respect of any other
         amounts  due under this  Agreement,  in respect of its portion of LIBOR
         Advances  or its  obligation  to make its  portion  of  LIBOR  Advances
         (except for changes in the rate or method of  calculation of tax on the
         revenues or net income of such Bank); or

                           (2)  shall  impose,  modify  or deem  applicable  any
         reserve  (including,  without  limitation,  any imposed by the Board of
         Governors of the Federal Reserve System,  but excluding any included in
         an applicable Eurodollar Reserve Percentage),  special deposit, capital
         adequacy,  assessment or other  requirement or condition against assets
         of,  deposits  with or for the  account  of, or  commitments  or credit
         extended  by,  any  Bank or  shall  impose  on any  Bank or the  London
         interbank borrowing market any other condition affecting its obligation
         to make its  portion of such LIBOR  Advances or its portion of existing
         Advances;



                                      -75-


<PAGE>



and the result of any of the  foregoing  is to increase the cost to such Bank of
making or  maintaining  any of its portion of LIBOR  Advances,  or to reduce the
amount of any sum received or  receivable  by such Bank under this  Agreement or
under its Note with respect thereto,  then, within ten (10) days after demand by
such Bank,  the Borrower  agrees to pay to such Bank such  additional  amount or
amounts as will  compensate such Bank for such increased  costs.  Each Bank will
promptly notify the Borrower and the Administrative  Agent of any event of which
it has knowledge,  occurring after the date hereof, which will entitle such Bank
to  compensation  pursuant to this Section  10.3 and will  designate a different
lending office if such designation will avoid the need for, or reduce the amount
of, such compensation and will not, in the sole reasonable judgment of such Bank
made in good faith, be otherwise disadvantageous to such Bank.

                  (b) Any Bank  claiming  compensation  under this  Section 10.3
shall  provide  the  Borrower  with a  written  certificate  setting  forth  the
additional  amount  or  amounts  to be paid  to it  hereunder  and  calculations
therefor in reasonable detail.  Such certificate shall be presumptively  correct
absent  manifest  error.  In  determining  such  amount,  such  Bank may use any
reasonable  averaging and attribution  methods. If any Bank demands compensation
under this Section  10.3,  the Borrower may at any time,  upon at least five (5)
Business Days' prior notice to such Bank,  prepay in full such Bank's portion of
the then outstanding  LIBOR Advances,  together with accrued interest thereon to
the date of prepayment, along with any reimbursement required under Section 2.10
hereof.  Concurrently with prepaying such portion of LIBOR Advances the Borrower
may,  whether or not then  entitled to make such  borrowing,  borrow a Base Rate
Advance,  or a LIBOR  Advance  not so  affected,  from such Bank,  and such Bank
shall, if so requested, make such Advance in an amount such that the outstanding
principal amount of the affected Note or Notes held by such Bank shall equal the
outstanding  principal  amount of such Note or Notes  immediately  prior to such
prepayment.

         Section  10.4  Effect  On Other  Advances.  If  notice  has been  given
pursuant to Section 10.1,  10.2 or 10.3 suspending the obligation of any Bank to
make its portion of any type of LIBOR Advance,  or requiring such Bank's portion
of LIBOR  Advances  to be repaid or  prepaid,  then,  unless and until such Bank
notifies the Borrower that the  circumstances  giving rise to such  repayment no
longer  apply,  all amounts  which would  otherwise  be made by such Bank as its
portion of LIBOR Advances shall,  unless otherwise notified by the Borrower,  be
made instead as Base Rate Advances.




                                      -76-


<PAGE>



                                   ARTICLE 11

                                  Miscellaneous

         Section 11.1 Notices.

                  (a) Except as otherwise expressly provided herein, all notices
and other  communications  under this  Agreement  and the other  Loan  Documents
(unless otherwise  specifically stated therein) shall be in writing and shall be
deemed to have been given  three (3)  Business  Days after  deposit in the mail,
designated as certified mail, return receipt requested,  postage-prepaid, or one
(1)  Business  Day after being  entrusted  to a reputable  commercial  overnight
delivery service for next day delivery,  or when sent on a Business Day prior to
5:00 p.m.  (New York  time) by  telecopy  addressed  to the party to which  such
notice is directed at its address  determined  as provided in this Section 11.1.
All notices and other  communications under this Agreement shall be given to the
parties hereto at the following addresses:

                (i)        If to the Borrower, to it at:

                           American Tower Systems, Inc.
                           6400 North Congress Avenue, Suite 1750
                           Boca Raton, Florida  33487
                           Attn:  James S. Eisenstein,
                                      Chief Executive Officer
                           and David U. Lee, Chief Financial Officer

                           with a copies to:

                           American Radio Systems Corporation
                           116 Huntington Avenue
                           Boston, Massachusetts  02111
                           Attn:  Joseph B. Winn, Chief Financial Officer

                           and

                           Sullivan & Worcester LLP
                           One Post Office Square
                           Boston, Massachusetts  02110
                           Attn:  Norman A. Bikales, Esq.



                                      -77-


<PAGE>



               (ii)        If to the Administrative Agent, to
                           it at:

                           Toronto Dominion (Texas), Inc.
                           909 Fannin Street, Suite 1700
                           Houston, Texas  77010
                           Attention:  Agency Department

                           with a copy to:

                           The Toronto-Dominion Bank
                           USA Division
                           31 West 52nd Street
                           New York, NY 10019-6101
                           Attn:  Director, Communications Finance

                           and

                           with a copy to:

                           Powell, Goldstein, Frazer & Murphy
                           Sixteenth Floor
                           191 Peachtree Street, N.E.
                           Atlanta, Georgia  30303
                           Attn:  Douglas S. Gosden, Esq.

              (iii)        If to the Banks, to them at the addresses set
                           forth beside their names on the signature pages
                           hereof.

The failure to provide  copies shall not affect the validity of the notice given
to the primary recipient.

                  (b) Any party  hereto may change the address to which  notices
shall be  directed  under this  Section  11.1 by giving  ten (10) days'  written
notice of such change to the other parties.

         Section 11.2 Expenses. The Borrower will promptly pay, or reimburse:

                  (a)   all   reasonable    out-of-pocket    expenses   of   the
Administrative Agent in connection with the preparation,  negotiation, execution
and  delivery  of  this  Agreement  and  the  other  Loan  Documents,   and  the
transactions contemplated hereunder and thereunder and the making of the initial
Advance  hereunder  (whether or not such  Advance is made),  including,  but not
limited to, the reasonable fees and disbursements of Powell, Goldstein, Frazer &
Murphy, special counsel for the Administrative Agent; and



                                      -78-


<PAGE>



                  (b) all  reasonable  out-of-pocket  costs and  expenses of the
Administrative  Agent and the Banks of  enforcement  under this Agreement or the
other Loan  Documents  and all  reasonable  out-of-pocket  costs and expenses of
collection if an Event of Default  occurs in the payment of the Notes,  which in
each case shall include  reasonable fees and  out-of-pocket  expenses of counsel
for the Administrative Agent and the Banks.

         Section 11.3  Waivers.  The rights and  remedies of the  Administrative
Agent and the Banks under this Agreement and the other Loan  Documents  shall be
cumulative  and not  exclusive  of any  rights  or  remedies  which  they  would
otherwise have. No failure or delay by the  Administrative  Agent,  the Majority
Banks, or the Banks, or any of them, in exercising any right, shall operate as a
waiver of such right. The  Administrative  Agent and the Banks expressly reserve
the right to  require  strict  compliance  with the terms of this  Agreement  in
connection  with any future  funding of a Request for Advance.  In the event the
Banks decide to fund a Request for Advance at a time when the Borrower is not in
strict  compliance with the terms of this Agreement,  such decision by the Banks
shall  not be  deemed  to  constitute  an  undertaking  by the Banks to fund any
further  Request for Advance or preclude the Banks or the  Administrative  Agent
from  exercising  any rights  available  under the Loan  Documents  or at law or
equity. Any waiver or indulgence granted by the Administrative Agent, the Banks,
or the Majority Banks,  shall not constitute a modification of this Agreement or
any other Loan Document,  except to the extent expressly provided in such waiver
or  indulgence,  or constitute a course of dealing at variance with the terms of
this  Agreement or any other Loan Document such as to require  further notice of
their intent to require  strict  adherence to the terms of this Agreement or any
other Loan Document in the future.

         Section  11.4  Set-Off.  In  addition  to any rights  now or  hereafter
granted  under  Applicable  Law and not by way of limitation of any such rights,
upon the occurrence of an Event of Default and during the continuation  thereof,
the  Administrative  Agent and each of the Banks are  hereby  authorized  by the
Borrower at any time or from time to time,  without notice to the Borrower or to
any other Person,  any such notice being hereby expressly waived, to set off and
to appropriate  and to apply any and all deposits  (general or special,  time or
demand, including, but not limited to, Indebtedness evidenced by certificates of
deposit,  in each case whether matured or unmatured) and any other  Indebtedness
at any time  held or owing by any Bank or  Administrative  Agent,  to or for the
credit or the  account of the  Borrower or any of its  Restricted  Subsidiaries,
against and on account of the obligations and liabilities of the Borrower to the
Banks  and  the  Administrative  Agent,  including,  but  not  limited  to,  all
Obligations and any other claims of any nature or description  arising out of or
connected with this Agreement, the


                                      -79-


<PAGE>



Notes or any  other  Loan  Document,  irrespective  of  whether  (a) any Bank or
Administrative  Agent  shall have made any demand  hereunder  or (b) any Bank or
Administrative  Agent shall have  declared the  principal of and interest on the
Loans and other  amounts due  hereunder  to be due and payable as  permitted  by
Section 8.2 and although such  obligations  and liabilities or any of them shall
be contingent or unmatured.  Upon direction by the Administrative Agent with the
consent of all of the Banks each Bank holding deposits of the Borrower or any of
its  Restricted  Subsidiaries  shall exercise its set-off rights as so directed;
and, within one (1) Business Day following any such setoff,  the  Administrative
Agent shall give notice thereof to the Borrower. Notwithstanding anything to the
contrary  contained in this Section  11.4,  no Bank shall  exercise any right of
offset  without  the  prior  consent  of  the  Majority  Banks  so  long  as the
Obligations  shall be secured by any real  property  or real  property  interest
including leaseholds located in the State of California, it being understood and
agreed that the provisions of this sentence are for the exclusive benefit of the
Banks,  may be amended,  modified or waived by the Majority Banks without notice
to or consent of the  Borrower or any  Subsidiary  of the Borrower and shall not
constitute  a waiver of any rights  against the  Borrower or any  Subsidiary  or
against any Collateral.

         Section 11.5 Assignment.

                  (a) The  Borrower may not assign or transfer any of its rights
or  obligations  hereunder,  under the Notes or under  any other  Loan  Document
without the prior written consent of each Bank.

                  (b) Each Bank may sell (i)  assignments  of any  amount of its
interest  hereunder to any Bank, or (ii)  assignments or  participations  of one
hundred  percent  (100%)  (or,  with the  consent  of the  Borrower,  a  smaller
percentage) of its interest hereunder to (A) one or more wholly-owned Affiliates
of such Bank (provided  that, if such Affiliate is not a financial  institution,
such Bank shall be obligated to repurchase  such assignment if such Affiliate is
unable to honor its obligations  hereunder),  or (B) any Federal Reserve Bank as
collateral  security  pursuant to  Regulation A of the Board of Governors of the
Federal Reserve System and any Operating Circular issued by such Federal Reserve
Bank (no assignment shall relieve such Bank from its obligations hereunder).

                  (c) Each of the Banks may at any time  enter  into  assignment
agreements  or  participations  with one or more  other  banks or other  Persons
pursuant to which each Bank may assign or  participate  its interest  under this
Agreement  and  the  other  Loan  Documents,  including,  its  interest  in  any
particular Advance or portion thereof, provided, that (1) all assignments (other
than


                                      -80-


<PAGE>



assignments  described  in clause  (b)  hereof)  shall be in  minimum  principal
amounts  of the  lesser of (X)  $5,000,000,  and (Y) the  amount of such  Bank's
Commitment (in a single  assignment  only), and (2) all assignments  (other than
assignments  described in clause (b) hereof) and participations  hereunder shall
be subject to the following additional terms and conditions:

                         (i) No  assignment  (except  assignments  permitted  in
         Section  11.5(b) hereof) shall be sold without the prior consent of the
         Administrative Agent and prior to the occurrence and continuation of an
         Event of Default, the consent of the Borrower, which consents shall not
         be unreasonably withheld;

                        (ii)  Any  Person   purchasing  a  participation  or  an
         assignment  of any portion of the Loans from any Bank shall be required
         to  represent  and warrant  that its  purchase  shall not  constitute a
         "prohibited transaction" (as defined in Section 4.1(m) hereof);

                       (iii) The  Borrower,  the Banks,  and the  Administrative
         Agent  agree  that  assignments   permitted  hereunder  (including  the
         assignment  of any  Advance  or portion  thereof)  may be made with all
         voting  rights,  and  shall  be  made  pursuant  to an  Assignment  and
         Assumption  Agreement  substantially  in the form of Exhibit N attached
         hereto.  An  administrative  fee of  $3,500  shall  be  payable  to the
         Administrative  Agent  by  the  assigning  Bank  at  the  time  of  any
         assignment under this Section 11.5(b);

                        (iv) No participation  agreement shall confer any rights
         under  this  Agreement  or any other  Loan  Document  to any  purchaser
         thereof,  or relieve any issuing Bank from any of its obligations under
         this Agreement,  and all actions  hereunder shall be conducted as if no
         such  participation  had  been  granted;  provided,  however,  that any
         participation  agreement  may  confer on the  participant  the right to
         approve or disapprove  decreases in the interest rate, increases in the
         principal  amount of the  Loans  participated  in by such  participant,
         decreases in fees,  extensions of the Maturity Date or other  principal
         payment  date  for  the  Loans  or of the  scheduled  reduction  of the
         Commitment and releases of Collateral;

                         (v)        Each Bank agrees to provide the
         Administrative Agent and the Borrower with prompt written
         notice of any issuance of participations in or assignments
         of its interests hereunder;

                        (vi)        No assignment, participation or other
         transfer of any rights hereunder or under the Notes shall be


                                      -81-


<PAGE>



         effected that would result in any interest requiring registration under
         the  Securities  Act of 1933, as amended,  or  qualification  under any
         state securities law;

                       (vii) No such assignment may be made to any bank or other
         financial   institution  (x)  with  respect  to  which  a  receiver  or
         conservator  (including,   without  limitation,   the  Federal  Deposit
         Insurance  Corporation,  the Resolution  Trust Company or the Office of
         Thrift  Supervision)  has been appointed or (y) that is not "adequately
         capitalized"  (as such term is defined in Section  131(b)(1)(B)  of the
         Federal Deposit Insurance  Corporation  Improvement Act as in effect on
         the Agreement Date); and

                      (viii) If  applicable,  each Bank  shall,  and shall cause
         each of its assignees  to,  provide to the  Administrative  Agent on or
         prior to the effective date of any  assignment an appropriate  Internal
         Revenue  Service form as required by  Applicable  Law  supporting  such
         Bank's or assignee's  position that no  withholding  by the Borrower or
         the  Administrative  Agent for U.S.  income tax payable by such Bank or
         assignee in respect of amounts  received by it  hereunder  is required.
         For purposes of this Agreement, an appropriate Internal Revenue Service
         form  shall  mean  Form  1001  (Ownership  Exemption  or  Reduced  Rate
         Certificate  of  the  U.S.  Department  of  Treasury),   or  Form  4224
         (Exemption from Withholding of Tax on Income Effectively Connected with
         the  Conduct  of a Trade or  Business  in the  United  States),  or any
         successor or related forms adopted by the relevant U.S.
         taxing authorities.

                  (d) Except as specifically set forth in Section 11.5(b) or (c)
hereof,  nothing  in this  Agreement  or the Notes,  expressed  or  implied,  is
intended  to or shall  confer on any Person  other than the  respective  parties
hereto and thereto and their  successors and assignees  permitted  hereunder and
thereunder  any benefit or any legal or equitable  right,  remedy or other claim
under this Agreement or the Notes.

                  (e) In the case of any  participation,  all amounts payable by
the Borrower under the Loan Documents shall be calculated and made in the manner
and to the parties hereto as if no such participation had been sold.

                  (f)      The provisions of this Section 11.5 shall not
apply to any purchase of participations among the Banks pursuant
to Section 2.11 hereof.

         Section 11.6 Accounting Principles. All references in this Agreement to
GAAP shall be to such  principles as in effect from time to time. All accounting
terms used herein without


                                      -82-


<PAGE>



definition  shall be used as defined under GAAP. All references to the financial
statements of the Borrower and to its  Operating  Cash Flow,  Total Debt,  Fixed
Charges,  Pro Forma Debt Service,  and other such terms shall be deemed to refer
to such  items  of the  Borrower  and its  Restricted  Subsidiaries,  on a fully
consolidated  basis. The Borrower shall deliver to the Banks at the same time as
the delivery of any quarterly or annual financial  statements  required pursuant
to Section 6.1 or 6.2 hereof,  as  applicable,  (a) a description  in reasonable
detail of any material variation between the application of GAAP employed in the
preparation  of such  statements  and the  application  of GAAP  employed in the
preparation of the next preceding quarterly or annual financial  statements,  as
applicable,  and  (b)  reasonable  estimates  of the  differences  between  such
statements arising as a consequence  thereof.  If, within thirty (30) days after
the delivery of the quarterly or annual financial  statements referred to in the
immediately  preceding  sentence,  the Majority Banks shall object in writing to
the Borrower's  determining compliance hereunder on such basis, (1) calculations
for the purposes of determining  compliance  hereunder  shall be made on a basis
consistent with those used in the preparation of the latest financial statements
as to which such objection  shall not have been made, or (2) if requested by the
Borrower, the Majority Banks will negotiate in good faith to amend the covenants
herein to give  effect to the changes in GAAP in a manner  consistent  with this
Agreement  (and  so  long as the  Borrower  complies  in  good  faith  with  the
provisions  of this  Section  11.6,  no Default or Event of Default  shall occur
hereunder solely as a result of such changes in GAAP).

         Section 11.7 Counterparts. This Agreement may be executed in any number
of counterparts,  each of which shall be deemed to be an original,  but all such
separate counterparts shall together constitute but one and the same instrument.

         Section  11.8  Governing  Law.  This  Agreement  and the Notes shall be
construed in  accordance  with and governed by the internal laws of the State of
New York  applicable to agreements  made and to be performed in New York. If any
action or proceeding  shall be brought by the  Administrative  Agent or any Bank
hereunder  or under any other Loan  Document  in order to  enforce  any right or
remedy under this  Agreement or under any Note or any other Loan  Document,  the
Borrower  hereby  consents and will, and the Borrower will cause each Restricted
Subsidiary  to,  submit to the  jurisdiction  of any state or  federal  court of
competent  jurisdiction sitting within the area comprising the Southern District
of New York on the date of this  Agreement.  The  Borrower,  for  itself  and on
behalf  of its  Restricted  Subsidiaries,  hereby  agrees  that,  to the  extent
permitted by Applicable Law,  service of the summons and complaint and all other
process which may be served in any such suit, action or


                                      -83-


<PAGE>



proceeding may be effected by mailing by registered  mail a copy of such process
to the offices of the  Borrower at the address  given in Section 11.1 hereof and
that personal service of process shall not be required.  Nothing herein shall be
construed to prohibit  service of process by any other method  permitted by law,
or the bringing of any suit, action or proceeding in any other jurisdiction. The
Borrower agrees that final judgment in such suit,  action or proceeding shall be
conclusive and may be enforced in any other jurisdiction by suit on the judgment
or in any other manner provided by Applicable Law.

         Section 11.9  Severability.  Any provision of this  Agreement  which is
prohibited or  unenforceable  in any  jurisdiction  shall be  ineffective to the
extent  of  such  prohibition  or  unenforceability   without  invalidating  the
remaining  provisions  hereof in that  jurisdiction or affecting the validity or
enforceability of such provision in any other jurisdiction.

         Section 11.10 Interest.

                  (a) In no event  shall the amount of  interest  due or payable
hereunder  or under the Notes  exceed the maximum  rate of  interest  allowed by
Applicable Law, and in the event any such payment is  inadvertently  made by the
Borrower or inadvertently received by the Administrative Agent or any Bank, then
such excess sum shall be credited as a payment of principal, unless the Borrower
shall notify the Administrative  Agent or such Bank, in writing,  that it elects
to have such excess sum returned forthwith. It is the express intent hereof that
the  Borrower  not pay and the  Administrative  Agent and the Banks not receive,
directly  or  indirectly  in any manner  whatsoever,  interest in excess of that
which may legally be paid by the Borrower under Applicable Law.

                  (b)  Notwithstanding the use by the Banks of the Base Rate and
the LIBOR as reference rates for the determination of interest on the Loans, the
Banks shall be under no obligation to obtain funds from any particular source in
order to charge  interest  to the  Borrower at  interest  rates  related to such
reference rates.

         Section 11.11 Table of Contents and Headings. The Table of Contents and
the  headings  of the  various  subdivisions  used  in  this  Agreement  are for
convenience  only and shall  not in any way  modify or amend any of the terms or
provisions  hereof,  nor be used in connection  with the  interpretation  of any
provision hereof.

         Section 11.12 Amendment and Waiver. Neither this Agreement nor any Loan
Document nor any term hereof or thereof may be


                                      -84-


<PAGE>



amended  orally,  nor may any  provision  hereof or thereof be waived orally but
only by an instrument  in writing  signed by or at the direction of the Majority
Banks and,  in the case of an  amendment,  by the  Borrower,  except that in the
event of (a) any increase in the amount of any Bank's portion of the Commitment,
(b) any delay or extension  in the terms of  repayment of the Loans  provided in
Section 2.5 or 2.7 hereof, (c) any reduction in principal,  interest or fees due
hereunder or postponement of the payment thereof without a corresponding payment
of such  principal,  interest or fee amount by the Borrower,  (d) any release of
any portion of the  Collateral  for the Loans,  except under Section 7.4 hereof,
(e) any waiver of any Default due to the failure by the  Borrower to pay any sum
due to any of the Banks hereunder, (f) any release of any Guaranty of all or any
portion of the  Obligations,  except in connection with a merger,  sale or other
disposition  otherwise  permitted  hereunder (in which case,  such release shall
require no further  approval by the Banks),  (g) any  amendment  to the pro rata
treatment of the Banks set forth in Section 2.11 hereof, or (h) any amendment of
this Section  11.12,  of the  definition  of Majority  Banks,  or of any Section
herein to the  extent  that such  Section  requires  action  by all  Banks,  any
amendment  or waiver or  consent  may be made only by an  instrument  in writing
signed by each of the Banks and, in the case of an  amendment,  by the Borrower.
Any amendment to any provision hereunder governing the rights,  obligations,  or
liabilities  of the  Administrative  Agent in its capacity as such,  may be made
only by an instrument in writing  signed by such affected  Person and by each of
the Banks.

         Section 11.13 Entire Agreement.  Except as otherwise expressly provided
herein,  this Agreement and the other documents described or contemplated herein
will embody the entire agreement and understanding  among the parties hereto and
thereto and supersede all prior  agreements and  understandings  relating to the
subject matter hereof and thereof.

         Section 11.14 Other Relationships. No relationship created hereunder or
under any  other  Loan  Document  shall in any way  affect  the  ability  of the
Administrative   Agent  and  each  Bank  to  enter  into  or  maintain  business
relationships   with  the  Borrower  or  any  of  its   Affiliates   beyond  the
relationships  specifically  contemplated  by this  Agreement and the other Loan
Documents.

         Section  11.15  Directly  or  Indirectly.  If  any  provision  in  this
Agreement refers to any action taken or to be taken by any Person, or which such
Person is prohibited  from taking,  such provision  shall be applicable  whether
such  action is taken  directly or  indirectly  by such  Person,  whether or not
expressly specified in such provision.



                                      -85-


<PAGE>



         Section  11.16  Reliance  on and  Survival of Various  Provisions.  All
covenants, agreements, statements, representations and warranties made herein or
in any  certificate  delivered  pursuant hereto (i) shall be deemed to have been
relied upon by the  Administrative  Agent and each of the Banks  notwithstanding
any  investigation  heretofore or hereafter made by them, and (ii) shall survive
the  execution  and  delivery of the Notes and shall  continue in full force and
effect  so  long  as  any  Note  is  outstanding   and  unpaid.   Any  right  to
indemnification  hereunder,  including,  without limitation,  rights pursuant to
Sections 2.10, 2.12,  5.12, 10.3 and 11.2 hereof,  shall survive the termination
of this Agreement and the payment and performance of all Obligations.

         Section 11.17 Senior Debt. The  Obligations are secured by the Security
Documents  and are  intended  by the  parties  hereto to be in  parity  with the
Interest  Hedge  Agreements  and  senior  in  right  of  payment  to  all  other
Indebtedness of the Borrower.

         Section   11.18   Obligations   Several.   The   obligations   of   the
Administrative Agent and each of the Banks hereunder are several, not joint.

         Section  11.19  Confidentiality.  The Banks shall hold all  non-public,
proprietary or  confidential  information  (which has been identified as such by
the  Borrower)  obtained  pursuant  to the  requirements  of this  Agreement  in
accordance with their customary procedures for handling confidential information
of this  nature  and in  accordance  with  safe  and  sound  banking  practices;
provided,  however,  the Banks may make  disclosure of any such  information  to
their examiners, Affiliates, outside auditors, counsel, consultants,  appraisers
and  other  professional  advisors  in  connection  with  this  Agreement  or as
reasonably  required by any proposed syndicate member or any proposed transferee
or  participant  in  connection  with the  contemplated  transfer of any Note or
participation therein or as required or requested by any governmental  authority
or representative thereof or in connection with the enforcement hereof or of any
Loan  Document or related  document or pursuant to legal process or with respect
to any litigation between or among the Borrower and any of the Banks, so long as
the person (other than any examiners)  receiving such  information is advised of
the provisions of this Section 11.19 and agrees to be bound thereby. In no event
shall any Bank be obligated or required to return any materials  furnished to it
by the Borrower. The foregoing provisions shall not apply to a Bank with respect
to information that (i) is or becomes  generally  available to the public (other
than through  such Bank),  (ii) is already in the  possession  of such Bank on a
nonconfidential  basis,  or (iii)  comes into the  possession  of such Bank in a
manner not known to such Bank to  involve a breach of a duty of  confidentiality
owing to the Borrower.


                                      -86-


<PAGE>




         Section  11.20  Termination  of  Agreement.   Notwithstanding  anything
contained in this  Agreement or any Loan Document to the contrary,  in the event
that the  Borrower  has failed to  satisfy  all of the  conditions  set forth in
Section 3.1 hereof on or prior to December 20, 1996, then at 5:00 p.m. (New York
time) all  obligations  of the Banks  hereunder,  pursuant to the  Commitment or
otherwise,  shall  immediately (and without notice of any kind) terminate and be
of no  force  and  effect;  provided,  however,  that  notwithstanding  any such
termination and irrespective of any such termination, the Borrower hereby agrees
to pay to the  Administrative  Agent, on or prior to December 20, 1996, the fees
required to be paid pursuant to Section  2.4(a)  hereof and hereby  acknowledges
that such Section 2.4(a) shall survive any such  termination of this  Agreement.
Promptly  following the  termination of the Banks'  obligations  pursuant to the
preceding  sentence,  the Banks shall  return the Notes to the Borrower and take
reasonable  steps (at the expense of the  Borrower)  as may be  requested by the
Borrower to cause any Liens granted under the Loan Documents to be released.

                                   ARTICLE 12

                              Waiver of Jury Trial

         Section  12.1 Waiver of Jury  Trial.  THE  BORROWER,  FOR ITSELF AND ON
BEHALF OF ITS  RESTRICTED  SUBSIDIARIES,  AND THE  ADMINISTRATIVE  AGENT AND THE
BANKS,  HEREBY AGREE, TO THE EXTENT  PERMITTED BY LAW, TO WAIVE AND HEREBY WAIVE
THE RIGHT TO A TRIAL BY JURY IN ANY COURT AND IN ANY ACTION OR PROCEEDING OF ANY
TYPE IN WHICH THE BORROWER, ANY OF THE BORROWER'S RESTRICTED  SUBSIDIARIES,  ANY
OF THE BANKS, THE ADMINISTRATIVE AGENT OR ANY OF THEIR RESPECTIVE  SUCCESSORS OR
ASSIGNS IS A PARTY, AS TO ALL MATTERS AND THINGS ARISING  DIRECTLY OR INDIRECTLY
OUT OF THIS  AGREEMENT,  ANY OF THE NOTES OR THE OTHER  LOAN  DOCUMENTS  AND THE
RELATIONS AMONG THE PARTIES LISTED IN THIS SECTION 12.1. EXCEPT AS PROHIBITED BY
LAW,  EACH  PARTY TO THIS  AGREEMENT  WAIVES  ANY RIGHTS IT MAY HAVE TO CLAIM OR
RECOVER IN ANY LITIGATION REFERRED TO IN THIS SECTION,  ANY SPECIAL,  EXEMPLARY,
PUNITIVE OR CONSEQUENTIAL  DAMAGES OR ANY DAMAGES OTHER THAN, OR IN ADDITION TO,
ACTUAL  DAMAGES.  EACH PARTY TO THIS  AGREEMENT (i)  CERTIFIES  THAT NEITHER ANY
REPRESENTATIVE,  AGENT OR ATTORNEY OF THE  ADMINISTRATIVE  AGENT OR ANY BANK HAS
REPRESENTED,  EXPRESSLY OR OTHERWISE,  THAT THE ADMINISTRATIVE AGENT OR ANY BANK
WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVERS AND
(ii) ACKNOWLEDGES THAT IT HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT AND EACH
OTHER  LOAN   DOCUMENT  BY,  AMONG  OTHER   THINGS,   THE  MUTUAL   WAIVERS  AND
CERTIFICATIONS  IN THIS SECTION.  THE PROVISIONS OF THIS SECTION HAVE BEEN FULLY
DISCLOSED  BY AND TO THE  PARTIES  AND THE  PROVISIONS  SHALL BE  SUBJECT  TO NO
EXCEPTIONS. NO PARTY HAS IN ANY WAY AGREED WITH OR REPRESENTED TO ANY OTHER


                                      -87-


<PAGE>



PARTY THAT THE  PROVISIONS  OF THIS  SECTION  WILL NOT BE FULLY  ENFORCED IN ALL
INSTANCES.

                  [Remainder of Page Intentionally Left Blank]



<PAGE>



         IN WITNESS WHEREOF,  the parties hereto have executed this Agreement or
caused it to be executed by their duly  authorized  officers,  all as of the day
and year first above written.


BORROWER:                                     AMERICAN TOWER SYSTEMS, INC., a
                                              Delaware corporation

                                              By:

                                                  Its:

[CORPORATE SEAL]                              Attest:

                                                  Its:


ADMINISTRATIVE AGENT:                         TORONTO DOMINION (TEXAS), INC.


                                              By:

                                                  Its:


BANKS:

ADDRESS:                                      TORONTO DOMINION (TEXAS), INC.

909 Fannin Street
Suite 1700                                    By:
Houston, Texas  77010
                                                  Its:


ADDRESS:                                      BANK OF MONTREAL

430 Park Avenue
New York, New York  10022                     By:

                                                  Its:



                                                    AMERICAN TOWER SYSTEMS, INC.
                                                                  LOAN AGREEMENT
                                                                SIGNATURE PAGE 1


<PAGE>


ADDRESS:                                      BANQUE PARIBAS

787 Seventh Avenue
32nd Floor                                    By:
New York, New York  10019
                                                  Its:


                                              By:

                                                  Its:


ADDRESS:                                      CREDIT SUISSE

12 East 49th Street
44th Floor                                    By:
New York, New York  10017
                                                  Its:


                                              By:

                                                  Its:


ADDRESS:                                      FLEET NATIONAL BANK

3rd Floor
Mail Code:  MAOF D03D                         By:
One Federal Street
Boston, Massachusetts  02110                      Its:


ADDRESS:                                      SIGNET BANK

7799 Leesburg Pike
Suite #500                                    By:
Falls Church, Virginia  22043
                                                 Its:


ADDRESS:                                      UNION BANK OF CALIFORNIA, N.A.

15th Floor
445 South Figueroa Street                     By:
Los Angeles, California  90071
                                                  Its:


                                                    AMERICAN TOWER SYSTEMS, INC.
                                                                  LOAN AGREEMENT
                                                                SIGNATURE PAGE 2


<PAGE>


                                    EXHIBIT A

                                     FORM OF
                           BORROWER'S PLEDGE AGREEMENT


         THIS BORROWER'S PLEDGE AGREEMENT (this "Agreement"), entered into as of
this 22nd day of November 1996, by and between  American Tower Systems,  Inc., a
Delaware corporation (the "Borrower"),  and Toronto Dominion (Texas),  Inc. (the
"Administrative  Agent") as administrative agent for itself and on behalf of the
Banks.


                              W I T N E S S E T H:


         WHEREAS,  the Borrower,  the Banks and the Administrative Agent are all
parties to that certain Loan Agreement dated as of even date herewith (the "Loan
Agreement"); and

         WHEREAS,  as a condition  precedent  to the  effectiveness  of the Loan
Agreement, the Borrower is required to execute and deliver this Agreement; and

         WHEREAS,  to secure the payment and performance of, among other things,
all  obligations  of the Borrower  under the Loan  Agreement and the  promissory
notes issued by the Borrower to the Banks thereunder (the "Notes"), the Borrower
and the  Administrative  Agent (on behalf of itself and the Banks),  have agreed
that the shares of capital stock (the "Stock")  owned by the Borrower in each of
the Subsidiaries of the Borrower listed on Schedule 1 attached hereto, which are
the only directly owned corporate Subsidiaries of the Borrower, shall be pledged
by the Borrower to the Administrative  Agent (on behalf of itself and the Banks)
to secure the Obligations;

         NOW,  THEREFORE,  in  consideration of the foregoing and for other good
and  valuable  consideration,  the receipt and  sufficiency  of which are hereby
acknowledged,  the parties hereto agree that capitalized terms used herein shall
have the  meanings  ascribed  to them in the Loan  Agreement  to the  extent not
otherwise defined or limited herein, and further agree as follows:

         1.  Warranty.  The  Borrower  hereby  represents  and  warrants  to the
Administrative  Agent and the  Banks  that,  except  for the  security  interest
created hereby, the Borrower owns the Stock, which constitutes the percentage of
the issued and outstanding  stock of the Subsidiaries as set forth on Schedule 1
attached  hereto,  free and clear of all Liens,  that the Stock is duly  issued,
fully paid and non-assessable,  and that the Borrower has the unencumbered right
to pledge the Stock.  In addition,  the  Borrower  represents  and  covenants as
follows: (1) the Stock represents all



<PAGE>



of  Borrower's  shares of capital stock in any  Subsidiary of the Borrower;  (2)
upon  possession  and retention of the Stock by the  Administrative  Agent,  the
Administrative  Agent shall have a valid and perfected  first priority  security
interest in the Stock,  securing the payment of the Obligations;  and (3) except
as  noted on  Schedule  2  attached  hereto,  the  Stock  represents  all of the
outstanding shares of stock issued by any direct Subsidiary of the Borrower.

         2. Security  Interest.  Subject to the provisions of Section 13 hereof,
the Borrower  hereby  unconditionally  grants and assigns to the  Administrative
Agent, for itself and on behalf of the Banks,  and their  respective  successors
and assigns,  a continuing  security interest in and security title to the Stock
and any other shares of capital stock of any Subsidiary of the Borrower obtained
in the future, and in each case, all certificates  representing such shares, all
rights, options,  warrant, stock or other securities or other property which may
hereafter  be  received,  receivable  or  distributed  in  respect of the Stock,
together with all proceeds of the foregoing,  including, without limitation, all
dividends, cash, notes, securities or other property from time to time acquired,
receivable  or  otherwise  distributed  in respect of, or in exchange  for,  the
foregoing,  all of which shall constitute  "Stock"  hereunder.  The Borrower has
delivered to and deposited with the Administrative Agent all of its right, title
and interest in and to the Stock,  together with  certificates  representing the
Stock,  and  undated  stock  powers  endorsed  in  blank,  as  security  for the
Obligations;  it being the  intention  of the  parties  hereto  that  beneficial
ownership of the Stock, including,  without limitation,  all voting,  consensual
and  dividend  rights,  shall remain in the Borrower  until the  occurrence  and
during  continuance of an Event of Default under the terms of the Loan Agreement
and  until  the   Administrative   Agent  shall   notify  the  Borrower  of  the
Administrative  Agent's  exercise  of voting  and  dividend  rights to the Stock
pursuant to Section 9 of this Agreement.

         3.       Additional Shares.  In the event that, during the term of
this Agreement:

                  (a)  any  stock  dividend,   stock  split,   reclassification,
         readjustment,  or  other  change  is  declared  or made in the  capital
         structure of any directly owned Subsidiary,  or any new stock is issued
         by such  Subsidiary,  or any new directly owned Subsidiary is formed or
         acquired,  all new, substituted,  and additional shares shall be issued
         to the Borrower and shall be promptly  delivered to the  Administrative
         Agent,  together  with undated  stock  powers  endorsed in blank by the
         Borrower,  and  shall  thereupon  constitute  Stock  to be  held by the
         Administrative Agent under the terms of this Agreement; and

                  (b) any subscriptions, warrants or any other rights or options
         shall be issued in  connection  with the Stock,  all new stock or other
         securities acquired through such subscriptions,


                                      - 2 -


<PAGE>



         warrants, rights or options by the Borrower shall be promptly delivered
         to  the  Administrative  Agent,  together  with  undated  stock  powers
         endorsed in blank,  and shall thereupon  constitute Stock to be held by
         the Administrative Agent under the terms of this Agreement.

         4. Default.  In the event of the  occurrence of an Event of Default and
so long as any such Event of Default is continuing, subject, however, to Section
13 hereof, the  Administrative  Agent may sell or otherwise dispose of the Stock
at a public or private sale or make other commercially reasonable disposition of
the  Stock or any  portion  thereof  after  fifteen  (15)  days'  notice  to the
Borrower,  and the  Administrative  Agent  and the  Banks  or any of  them,  may
purchase the Stock or any portion  thereof at any public  sale.  The proceeds of
the public or private sale or other  disposition  shall be applied  first to the
costs  of the  Administrative  Agent  incurred  in  connection  with  the  sale,
expressly including,  without limitation,  any costs under Section 7 hereof, and
then to the  Obligations  as  provided in the Loan  Agreement.  In the event the
proceeds  of the sale or other  disposition  of the  Stock are  insufficient  to
satisfy  the  Obligations,  the  Borrower  shall  remain  liable  for  any  such
deficiency.  The Borrower waives, to the extent permitted by Applicable Law, the
rights of equity of redemption,  appraisal,  notice of acceptance,  presentment,
demand and marshalling, to the extent applicable.

         5.  Additional  Rights of Secured Party.  In addition to its rights and
privileges under this Agreement,  the Administrative  Agent, on behalf of itself
and the Banks,  shall have all the rights,  powers and  privileges  of a secured
party  under  the  Uniform  Commercial  Code  as in  effect  in  any  applicable
jurisdiction and other Applicable Law.

         6.  Return  of  Stock  to the  Borrower.  Upon  payment  in full of all
principal  and interest on the Notes,  full  performance  by the Borrower of all
covenants, undertakings and obligations under the Loan Agreement, the Notes, and
the other Loan Documents,  and  satisfaction  in full of any other  Obligations,
other than the  Obligations  which survive the termination of the Loan Agreement
as provided in Section 11.16 of the Loan  Agreement,  and after such time as the
Banks shall have no  obligation  to make any further  Advances to the  Borrower,
this Agreement  shall  terminate and the  Administrative  Agent shall return the
remaining Stock and all rights received by the Administrative  Agent as a result
of its possessory interest in the Stock to the Borrower.

         7.  Disposition  of Stock by  Administrative  Agent.  The  Stock is not
registered or qualified  under the various  Federal or state  securities laws of
the United States and disposition thereof after default may be restricted to one
or more private  (instead of public) sales.  The Borrower  understands that upon
such disposition, the Administrative Agent may approach only a


                                      - 3 -


<PAGE>



restricted  number of potential  purchasers and further  understands that a sale
under such circumstances may yield a lower price for the Stock than if the Stock
were registered and qualified  pursuant to Federal and state securities laws and
sold on the open market.
The Borrower, therefore, agrees that:

                  (a) if the Administrative  Agent shall,  pursuant to the terms
         of this Agreement, sell or cause the Stock or any portion thereof to be
         sold at a private sale, the  Administrative  Agent shall have the right
         to rely upon the  advice  and  opinion  of any  national  brokerage  or
         investment   firm  having   recognized   expertise  and  experience  in
         connection with shares of communications tower companies (but shall not
         be  obligated to seek such advice and the failure to do so shall not be
         considered in determining the commercial reasonableness of such action)
         as to the best  manner in which to expose  the Stock for sale and as to
         the best price reasonably obtainable at the private sale thereof; and

                  (b) that such reliance  shall be conclusive  evidence that the
         Administrative  Agent has handled such  disposition  in a  commercially
         reasonable manner absent manifest error.

         8.  Borrower's  Obligations  Absolute.  The obligations of the Borrower
under  this  Agreement  shall be direct and  immediate  and not  conditional  or
contingent  upon the pursuit of any  remedies  against the Borrower or any other
Person,  nor against  other  security or liens  available to the  Administrative
Agent or any Bank.  The  Borrower  hereby  waives any right to  require  that an
action be brought  against any other  Person or to require that resort be had to
any other  security or to any  balance of any  deposit  account or credit on the
books  of the  Administrative  Agent or any of the  Banks in favor of any  other
Person  prior to the  exercise  of  remedies  hereunder,  or to  require  action
hereunder prior to resort by the  Administrative  Agent to any other security or
collateral for the Notes and the other Obligations. No amendment,  modification,
waiver,  transfer or  renewal,  extension,  assignment  or  termination  of this
Agreement  or of the Loan  Agreement  or of any other Loan  Document,  or of any
instrument  or document  executed  and  delivered  by the  Borrower or any other
obligor  with  respect to the  Obligations  to the Banks and the  Administrative
Agent,  or any of  them,  nor  additional  advances  made by the  Banks  and the
Administrative Agent, or any of them, to the Borrower, nor the taking of further
security,  nor the retaking or  re-delivery  or release of the Collateral or any
other collateral or guaranty to the Borrower by the Banks and the Administrative
Agent,  or any of them, nor any lack of validity or  enforceability  of any Loan
Document  or  any  term  thereof,  nor  any  other  act  of the  Banks  and  the
Administrative  Agent,  or any of them,  shall  release  the  Borrower  from any
Obligation,   except  a  release  or  discharge   executed  in  writing  by  the
Administrative  Agent in accordance with the Loan Agreement with respect to such
Obligation or upon full payment and satisfaction of all Obligations. Neither the


                                      - 4 -


<PAGE>



Administrative  Agent  nor any  Bank  shall,  by any  act,  delay,  omission  or
otherwise,  be  deemed to have  waived  any of its or their  rights or  remedies
hereunder,  unless such  waiver is in writing  and signed by the  Administrative
Agent in accordance  with the Loan Agreement and then only to the extent therein
set forth. A waiver by the Banks and the  Administrative  Agent, or any of them,
of any right or remedy on any  occasion  shall not be  construed as a bar to the
exercise of any such right or remedy which any such Person would  otherwise have
had on any other occasion.

         9.       Voting Rights.

                  (a) For so long as the Notes or any other  Obligations  remain
         unpaid,  after and during the continuation of an Event of Default,  but
         subject to the provisions of Section 13 hereof,  (i) the Administrative
         Agent may, upon fifteen (15) days' prior written notice to the Borrower
         of its intention to do so,  exercise all voting  rights,  and all other
         ownership or consensual rights of the Stock, but under no circumstances
         is the Administrative Agent obligated by the terms of this Agreement to
         exercise  such  rights,  and  (ii) the  Borrower  hereby  appoints  the
         Administrative  Agent,  which  appointment  shall be  effective  on the
         fifteenth   (15th)   day   following   the  giving  of  notice  by  the
         Administrative  Agent as provided in the foregoing Section 9(a)(i), the
         Borrower's true and lawful  attorney-in-fact  and IRREVOCABLE  PROXY to
         vote the Stock in any manner the  Administrative  Agent deems advisable
         for or against all matters  submitted  or which may be  submitted  to a
         vote of shareholders.  The power-of-attorney  granted hereby is coupled
         with an interest and shall be irrevocable.

                  (b) For so long as the  Borrower  shall have the right to vote
         the Stock, the Borrower  covenants and agrees that it will not, without
         the prior written consent of the Administrative Agent, vote or take any
         consensual  action with respect to the Stock which would  constitute an
         Event of Default.

         10.      Notices.  All notices and other communications required
or permitted hereunder shall be in writing, and shall be given in
the manner and at the addresses set forth in Section 11.1 of the
Loan Agreement.

         11.  Binding  Agreement.  The  provisions  of this  Agreement  shall be
construed and interpreted,  and all rights and obligations of the parties hereto
determined,  in  accordance  with  the  internal  laws of the  State of New York
applicable to contracts made and to be performed in the State of New York.  This
Agreement,  together  with all  documents  referred to herein,  constitutes  the
entire  agreement  between the  parties  with  respect to the matters  addressed
herein  and  may  not  be  modified   except  by  a  writing   executed  by  the
Administrative  Agent and the Borrower and delivered by the Administrative Agent
to the Borrower.



                                      - 5 -


<PAGE>



         12. Severability. If any paragraph or part thereof shall for any reason
be held or  adjudged  to be invalid,  illegal or  unenforceable  by any court of
competent  jurisdiction,  such paragraph or part thereof so adjudicated invalid,
illegal or unenforceable shall be deemed separate, distinct and independent, and
the remainder of this Agreement  shall remain in full force and effect and shall
not be affected by such holding or adjudication.

         13.  FCC  Compliance.  Notwithstanding  anything  herein  which  may be
construed to the contrary,  no action shall be taken by the Administrative Agent
which may require the consent or approval of the FCC,  and the proxy  granted in
Section 9(a) shall not become  effective,  unless and until all  requirements of
the  Communications  Act  requiring the consent to or approval of such action by
the FCC have been satisfied.  The Borrower covenants that,  following and during
the  continuation  of an Event of Default,  upon  request of the  Administrative
Agent, it will cause to be filed such applications and take such other action as
may be reasonably  requested by the  Administrative  Agent to obtain  consent or
approval of the FCC to any action  contemplated  by this  Agreement  and to give
effect to the security interest of the Administrative Agent, including,  without
limitation,  the  execution  of an  application  for  consent  by the  FCC to an
assignment  or transfer  involving a change in ownership or control  pursuant to
the provisions of the Communications Act.

         14.      Counterparts.  This Agreement may be executed in multiple
counterparts, each of which shall be deemed to be an original, but
all such separate counterparts shall together constitute but one
and the same instrument.

         15.  Administrative  Agent.  Each reference herein to any right granted
to, benefit  conferred upon or power exercisable by the  "Administrative  Agent"
shall be a  reference  to the  Administrative  Agent for the  benefit of all the
Banks,  and each action taken or right  exercised  hereunder  shall be deemed to
have been so taken or exercised by the  Administrative  Agent for the benefit of
and on behalf of all the Banks.




                                      - 6 -


<PAGE>


         IN WITNESS WHEREOF,  the undersigned  parties hereto have executed this
Agreement by and through their duly authorized officers,  as of the day and year
first above written.


BORROWER:                                     AMERICAN TOWER SYSTEMS, INC.,
                                              a Delaware corporation


                                              By:

[CORPORATE SEAL]                                  Title:

                                              Attest:

                                                  Title:

Address:

American Tower Systems, Inc.
6400 North Congress Avenue
Suite 1750
Boca Raton, Florida  33482
Attention:  David U. Lee
Telecopy:  610/341-1835


ADMINISTRATIVE AGENT:                         TORONTO DOMINION (TEXAS), INC.,
                                                       as Administrative Agent


                                              By:

                                                  Title:


SCHEDULES

  Schedule 1  -  Shares Pledged Pursuant to Pledge Agreement
  Schedule 2  -  Outstanding Shares of Stock

BORROWER'S PLEDGE AGREEMENT
SIGNATURE PAGE 1

<PAGE>


                                    EXHIBIT B

                                     FORM OF
                           BORROWER SECURITY AGREEMENT


         THIS BORROWER  SECURITY  AGREEMENT (this  "Agreement")  dated as of the
22nd day of November  1996,  by and between  American  Tower  Systems,  Inc.,  a
Delaware  corporation (the "Borrower"),  and Toronto Dominion (Texas),  Inc., as
administrative agent (the "Administrative Agent") for itself and the Banks.


                              W I T N E S S E T H:


         WHEREAS,  the Borrower,  the Banks and the Administrative Agent are all
parties to that certain Loan Agreement dated as of even date herewith (the "Loan
Agreement"); and

         WHEREAS,  as a condition  precedent  to the  effectiveness  of the Loan
Agreement, the Borrower is required to execute and deliver this Agreement;

         NOW,  THEREFORE,  in  consideration of the foregoing and for other good
and  valuable  consideration,  the receipt and  sufficiency  of which are hereby
acknowledged,  the parties hereto agree that capitalized terms used herein shall
have the  meanings  ascribed  to them in the Loan  Agreement  to the  extent not
otherwise defined or limited herein, and further agree as follows:

                  1. Grant of Security  Interest.  Subject to the  provisions of
Sections 23 and 25 hereof,  and to the extent permitted by Applicable Law in the
case of the Licenses,  the Borrower hereby unconditionally grants and assigns to
the  Administrative  Agent  (for  itself and the  Banks) a  continuing  security
interest in and  security  title to  (hereinafter  referred to as the  "Security
Interest")  all of its  property  and  assets  and  all  additions  thereto  and
replacements  thereof,  and all other  property  whether now owned or  hereafter
created, acquired or reacquired by the Borrower, including:

Inventory

         All of the Borrower's  inventory and supplies of whatsoever  nature and
kind and wheresoever  situated,  including,  without limitation,  raw materials,
components,  work in process,  finished goods,  goods in transit and packing and
shipping  materials,  accretions  and  accessions  thereto,  trust  receipts and
similar documents covering the same products (the "Inventory");




<PAGE>



Accounts

         All right to payment for goods sold or leased or for services rendered,
expressly  including,  without limitation,  in connection with owning,  leasing,
managing and operating communications tower facilities, whether or not earned by
performance,  including,  without  limitation,  all agreements with and sums due
from  customers  and  other  Persons,  and  all  books  and  records  recording,
evidencing or relating to such rights or any part thereof (the "Accounts");

Equipment

         All machinery,  equipment and supplies  (installed and uninstalled) not
included in  Inventory  above,  including  motor  vehicles  and  accretions  and
accessions  thereto;  and  expressly  including,  without  limitation,   towers,
antennas  and  equipment  located  at  communications   tower  facilities;   any
distribution systems and all components thereof, including,  without limitation,
hardware,  cables,  fiber optic cables,  switches,  CODECs,  computer equipment,
amplifiers,  and associated devices;  and any other equipment used in connection
with the Borrower's business (the "Equipment");

Contracts and Leases

         All  assignable  (a)  construction  contracts,   subscriber  contracts,
customer service agreements,  management  agreements,  rights of way, easements,
pole attachment  agreements,  transmission  capacity agreements,  public utility
contracts  and other  agreements  to which the Borrower is a party,  whether now
existing or hereafter arising,  including,  without limitation,  those listed on
Exhibit A hereto (the  "Contracts");  (b) lease agreements for personal property
to which the  Borrower is a party,  whether now  existing or  hereafter  arising
including  without  limitation  those listed on Exhibit B hereto (the "Leases");
and (c) other  contracts and  contractual  rights,  remedies or  provisions  now
existing or hereafter arising in favor of the Borrower (the "Other Contracts");

General Intangibles

         All general intangibles including personal property not included above,
such as, without limitation, all goodwill,  trademarks,  trademark applications,
trade names, trade secrets, industrial designs, other industrial or intellectual
property or rights therein,  whether under license or otherwise,  claims for tax
refunds, and tax refund amounts (the "Intangibles");



                                       -2-


<PAGE>



Licenses

         To the extent  permitted by  Applicable  Law and subject to Sections 23
and 25 hereof,  all  franchises,  permits and operating  rights  authorizing  or
relating to the Borrower's rights to operate and maintain  communications  tower
facilities or similar business including,  without limitation, the Licenses, all
as more particularly described on Exhibit C attached hereto;

Furniture and Fixtures

         All furniture and fixtures in which the Borrower has an
interest (the "Furniture and Fixtures");

Miscellaneous Items

         All goods, chattel paper, documents,  instruments,  supplies, choses in
action,  claims,  money,  deposits,  certificates  of  deposit,  stock  or share
certificates,  and  licenses  and other  rights  in  intellectual  property  not
included above (the "Miscellaneous Items"); and

Proceeds

         All  proceeds  of any of the above,  and all  proceeds  of any loss of,
damage to or destruction of the above,  whether insured or not insured,  and all
other  proceeds of any sale,  lease or other  disposition  of any  property  (or
interest therein) referred to above (including, without limitation, the proceeds
from the sale of any  License),  together  with all  proceeds of any policies of
insurance  covering  any or all of the  above,  the  proceeds  of any  award  in
condemnation with respect to any of the property of the Borrower, any rebates or
refunds, whether for taxes or otherwise,  together with all proceeds of any such
proceeds (the "Proceeds").

         The Inventory, Accounts, Equipment, Contracts, Other
Contracts, Leases, Intangibles, Licenses, Furniture and Fixtures,
Miscellaneous Items, and Proceeds, as described above, are
hereinafter collectively referred to as the "Collateral."

         This  Agreement  and the  Security  Interest  secure  the  payment  and
performance of the Obligations (as defined in the Loan Agreement).

                  2. Further  Assurances.  The Borrower  hereby  authorizes  the
Administrative  Agent to file such financing statements and such other documents
as the  Administrative  Agent may  reasonably  require to protect or perfect the
interest of the Banks and the  Administrative  Agent in the Collateral,  and the
Borrower further irrevocably appoints the Administrative Agent as the Borrower's
attorney-in-fact,  with a power of attorney to execute on behalf of the Borrower
such Uniform Commercial Code


                                       -3-


<PAGE>



(the "UCC") financing statement forms as the Administrative  Agent may from time
to time deem  necessary or desirable to protect or perfect such  interest in the
Collateral.  Such power of  attorney is coupled  with an  interest  and shall be
irrevocable.  In  addition,  the Borrower  agrees to do,  execute and deliver or
cause to be done,  executed and delivered  all such further acts,  documents and
things as the  Administrative  Agent may  reasonably  require for the purpose of
perfecting or protecting  the rights of the Banks and the  Administrative  Agent
hereunder or  otherwise  giving  effect to this  Agreement,  all  promptly  upon
request therefor.

                  3.  Representations and Warranties.  The Borrower
represents and warrants to the Banks and the Administrative Agent
that:

                  (a) Exhibit A attached hereto and incorporated  herein by this
         reference  sets forth a complete and accurate  list of the Contracts in
         effect on the date hereof which provide for  aggregate  payments to the
         Borrower over the life of any single  Contract in excess of $250,000 or
         which are  otherwise  material to the  Borrower,  and the Borrower will
         furnish copies thereof to the Banks and the  Administrative  Agent upon
         the request of the Administrative Agent;

                  (b) Exhibit B attached hereto and incorporated  herein by this
         reference  sets  forth a  complete  and  accurate  list  of all  Leases
         providing for  aggregate  payments to the Borrower over the life of any
         single Lease in excess of  $100,000,  to which the Borrower is party in
         effect on the date hereof, and the Borrower will furnish copies thereof
         to the Banks  and the  Administrative  Agent  upon the  request  of the
         Administrative Agent; and

                  (c) Exhibit C attached hereto and incorporated  herein by this
         reference  sets forth a complete and  accurate  list of the Licenses in
         effect on the date hereof.

                  4. Representations and Warranties Concerning  Collateral.  The
Borrower further  represents and warrants that (a) the Security  Interest in the
Collateral  granted  hereunder  shall  constitute  at all  times a  valid  first
priority  security  interest  (subject only to Permitted  Liens),  vested in the
Administrative  Agent, in and upon the Collateral,  free of any Liens except for
Permitted Liens, (b) the location of the Inventory and Equipment is as set forth
in Schedule 1 hereto, and (c) none of the Accounts are represented by promissory
notes or other  instruments.  The Borrower  shall take or cause to be taken such
acts and  actions  as shall be  necessary  or  appropriate  to  assure  that the
Security  Interest in the Collateral  shall not become  subordinate or junior to
the  security  interests,  liens or  claims of any  other  Person,  and that the
Collateral  shall not  otherwise  be or become  subject to any Lien,  except for
Permitted Liens.


                                       -4-


<PAGE>




                  5.  Location  of  Books  and  Records.  The  Borrower  further
represents  and  warrants  that it now keeps all of its records  concerning  its
Accounts,  Contracts,  Leases,  Other  Contracts,  and  Intangibles at its chief
executive office, which is the address set forth with respect to the Borrower in
Section 11.1 of the Loan  Agreement.  The Borrower  covenants and agrees that it
shall not keep any of such records at any other  address,  unless written notice
thereof is given to the Administrative  Agent at least thirty (30) days prior to
the  creation of any new address for the keeping of such  records.  The Borrower
further  agrees  that it shall  promptly  advise the  Administrative  Agent,  in
writing making reference to this Section 4 of this Agreement,  of the opening of
any material new place of business,  the closing of any existing  material place
of  business,  or any  change in the  location  of the place  where it keeps the
Collateral or of its chief executive officer.

                  6.       Collateral Not Fixtures.  The parties intend that,
to the extent permitted by Applicable Law, the Collateral shall
remain personal property irrespective of the manner of its
attachment or affixation to realty.

                  7. Covenants Regarding  Collateral.  Any and all injury to, or
loss or  destruction  of, the Collateral  shall be at the  Borrower's  risk, and
shall not release the  Borrower  from its  obligations  hereunder.  The Borrower
agrees not to sell,  transfer,  assign,  dispose of, mortgage,  grant a security
interest in, or encumber  any of the  Collateral  except as permitted  under the
Loan  Agreement.  The Borrower  agrees to maintain in force such  insurance with
respect to the Collateral as is required under the Loan Agreement.  The Borrower
agrees to pay all required taxes,  liens,  and assessments  upon the Collateral,
its use or operation, as required under the Loan Agreement. The Borrower further
agrees that the Administrative Agent may, but shall in no event be obligated to,
upon prior written notice to the Borrower,  insure any of the Collateral in such
form and amount as the  Administrative  Agent may deem necessary or desirable if
the Borrower fails to obtain  insurance as required by the Loan  Agreement,  and
that the  Administrative  Agent may pay or  discharge  any taxes if the Borrower
fails to pay such taxes as required by the Loan  Agreement  or Liens  (which are
not Permitted  Liens) on any of the  Collateral,  and the Borrower agrees to pay
any such sum so  expended  by the  Administrative  Agent,  with  interest at the
Default Rate,  and such amounts shall be deemed to be a part of the  Obligations
secured by the Collateral under the terms of this Agreement.

                  8. Covenants Regarding Contracts,  Other Contracts and Leases.
The  Borrower  shall (i) fulfill,  perform and observe  each and every  material
condition and covenant contained in any of the Contracts, the Other Contracts or
the Leases  other than those being  contested  in good faith or unless the other
party thereto is in default, (ii) give prompt notice to the Administrative


                                       -5-


<PAGE>



Agent of any claim of material  default  under any Contract,  Other  Contract or
Lease  given to the  Borrower  or by the  Borrower,  (iii) at the sole  cost and
expense of the  Borrower,  enforce the  performance  and  observance of each and
every material covenant and condition of the Contracts,  the Other Contracts and
the Leases,  and (iv)  appear in and defend any action  growing out of or in any
manner  connected  with any Contract,  Other  Contract or Lease other than those
which in the Borrower's  reasonable  business judgment are no longer in the best
interest  of the  Borrower  to  enforce  and  which  have been  approved  by the
Administrative  Agent.  The rights and interests  granted to the  Administrative
Agent hereunder include all of the Borrower's rights and title (i) to modify the
Contracts,  the Other Contracts and the Leases, (ii) to terminate the Contracts,
the  Other  Contracts  and the  Leases,  and  (iii)  to  waive  or  release  the
performance or observance of any  obligation or condition of the Contracts,  the
Other Contracts and the Leases; provided,  however, that the Borrower shall have
the right to exercise these rights in a fashion  consistent  with this Agreement
prior to any Event of Default and that these  rights  shall not be  exercised by
the  Administrative  Agent prior to the occurrence and during the continuance of
an Event of Default.

                  9. Remedies.  Upon the occurrence and during the  continuation
of an Event of Default  the Banks and the  Administrative  Agent shall have such
rights and remedies as are set forth in the Loan  Agreement and herein,  all the
rights,  powers and  privileges of a secured party under the UCC of the State of
New York  and any  other  applicable  jurisdiction,  and all  other  rights  and
remedies available to the Banks and the Administrative Agent, or any of them, at
law or in equity.  The Borrower  covenants and agrees that any  notification  of
intended disposition of any Collateral, if such notice is required by law, shall
be deemed  reasonably and properly given if given in the manner  provided for in
Section 20 hereof at least ten (10) days prior to such  disposition.  Under such
circumstances,  the Administrative Agent shall have the right to the appointment
of a receiver for the  properties  and assets of the Borrower,  and the Borrower
hereby  consents  to such right and to such  appointment  and hereby  waives any
objection  the Borrower  may have thereto and hereby  waives the right to have a
bond or other security posted by the Administrative Agent or any other Person in
connection  therewith.  The Borrower agrees, after the occurrence and during the
continuation of an Event of Default, to take any actions that the Administrative
Agent may  reasonably  request  in order to enable the  Administrative  Agent to
obtain and enjoy the full  rights  and  benefits  granted to the  Administrative
Agent under this Agreement and the other Loan  Documents.  Without  limiting the
generality of the foregoing,  the Borrower  shall,  at the  Borrower's  cost and
expense, use its reasonable best efforts to assist in obtaining all approvals of
the FCC which are then required by law for or in  connection  with any action or
transaction contemplated by this Agreement or Article 9 of the


                                       -6-


<PAGE>



UCC as in effect in any  applicable  jurisdiction,  and,  at the  Administrative
Agent's  request,  prepare,  sign  and  file  with  the  FCC the  assignor's  or
transferor's  portion of any  application  or  applications  for  consent to the
assignment  of  the  Licenses  or  transfer  of  control  thereof  necessary  or
appropriate  under the FCC's  rules for  approval of any sale or transfer of the
Licenses in  connection  with the  Administrative  Agent's  exercise of remedies
under  this  Agreement.  The  Administrative  Agent  shall  have the  right,  in
connection with the issuance of any order for relief in a bankruptcy proceeding,
to petition the  bankruptcy  court for the transfer of control or  assignment of
the Licenses to a receiver,  trustee,  transferee, or similar official or to any
purchaser of the Collateral pursuant to any public or private sale,  foreclosure
or other  exercise of remedies  available to the  Administrative  Agent,  all as
permitted  by  Applicable  Law. All amounts  realized or  collected  through the
exercise of remedies  hereunder  shall be applied to the Obligations as provided
in the Loan Agreement.

                  10.  Notification of Account Debtors.  Upon the occurrence and
during the  continuation of an Event of Default,  the  Administrative  Agent may
notify the account  debtors that all payments with respect to Accounts are to be
paid directly to the Administrative  Agent and any amount thereafter paid to the
Borrower  shall be  received  in trust by the  Borrower  for the  benefit of the
Administrative  Agent and  segregated  from other funds of the Borrower and paid
over to the  Administrative  Agent  in the  form  received  (together  with  any
necessary endorsements).

                  11. Remedies of Administrative  Agent. Upon the occurrence and
during the continuation of an Event of Default,  and after written notice to the
Borrower,  the  Administrative  Agent or its designee may proceed to perform any
and all of the  obligations  of the Borrower  contained in any of the Contracts,
Other  Contracts  or Leases  and  exercise  any and all  rights of the  Borrower
therein  contained as fully as the Borrower  itself could.  The Borrower  hereby
appoints  the  Administrative   Agent  its   attorney-in-fact,   with  power  of
substitution, to take such action, execute such documents, and perform such work
as the  Administrative  Agent may deem appropriate in exercise of the rights and
remedies granted the Banks and the Administrative  Agent, or any of them, herein
or in any other Loan Document.  The power of attorney  granted herein is coupled
with an interest and shall be irrevocable.

                  12.  Additional  Remedies.  Upon the occurrence and during the
continuation  of an Event of  Default,  should the  Borrower  fail to perform or
observe  any  covenant  or comply  with any  condition  contained  in any of the
Contracts, the Other Contracts or the Leases, then the Administrative Agent may,
but without  obligation  to do so and without  releasing  the Borrower  from its
obligation  to do so, and after  written  notice to the  Borrower,  perform such
covenant or condition and, to the extent


                                       -7-


<PAGE>



that the  Administrative  Agent  shall  incur  any  reasonable  costs or pay any
expenses in connection therewith,  including any reasonable costs or expenses of
litigation  associated  therewith,  such costs,  expenses  or payments  shall be
included in the  Obligations  secured  hereby and shall bear  interest  from the
payment of such costs or  expenses  by the  Administrative  Agent at the Default
Rate. Neither the Administrative  Agent nor any Bank shall be obliged to perform
or discharge any  obligation  of the Borrower  under any of the  Contracts,  the
Other Contracts or the Leases.

         13.  Administrative  Agent May Collect  Accounts.  The Borrower  hereby
further  appoints the  Administrative  Agent,  effective upon the occurrence and
during continuation of an Event of Default as its  attorney-in-fact,  with power
of substitution,  with authority to collect all Accounts, to endorse the name of
the  Borrower  on any  note,  acceptance,  check,  draft,  money  order or other
evidence of debt or of payment which constitutes a portion of the Collateral and
which may come into the possession of the Banks and the Administrative Agent, or
any of them,  and  generally to do such other things and acts in the name of the
Borrower  with respect to the  Collateral  as are  necessary or  appropriate  to
protect or  enforce  the rights  hereunder  of the Banks and the  Administrative
Agent. The Borrower further authorizes the Administrative Agent,  effective upon
the occurrence and during the continuation of an Event of Default, to compromise
and settle or to sell, assign or transfer or to ask,  collect,  receive or issue
any and all claims  possessed by the Borrower which  constitute a portion of the
Collateral,  all in the name of the Borrower.  After  deducting  all  reasonable
expenses and charges (including the  Administrative  Agent's attorneys' fees) of
retaking,  keeping, storing and selling the Collateral, the Administrative Agent
may apply the  proceeds  in  payment of any of the  Obligations  in the order of
application  set  forth in the Loan  Agreement.  The power of  attorney  granted
herein is coupled with an interest and shall be irrevocable. The Borrower agrees
that if steps  are  taken by the  Administrative  Agent to  enforce  its  rights
hereunder,  or to realize upon any of the Collateral,  the Borrower shall pay to
the  Administrative  Agent the amount of the  Administrative  Agent's reasonable
costs,  including  attorneys'  fees, and the  Borrower's  obligation to pay such
amounts shall be deemed to be a part of the Obligations secured hereunder.  Upon
the occurrence and during the continuation of an Event of Default,  the Borrower
shall  segregate  all  proceeds  of any  Collateral  from  other  assets  of the
Borrower.

         14. Indemnification. The Borrower shall indemnify and hold harmless the
Administrative  Agent and each Bank,  and any other Person acting  hereunder for
all losses,  costs,  damages,  fees and expenses whatsoever  associated with the
exercise  of the  powers  of  attorney  granted  herein  and shall  release  the
Administrative  Agent and each Bank, and any other Person acting  hereunder from
all liability whatsoever for the exercise of the foregoing powers


                                       -8-


<PAGE>



of attorney and all actions taken pursuant thereto,  except, in either event, in
the case of bad faith,  gross  negligence  or willful  misconduct  by the Person
seeking indemnification.

         15.  Remedies  Cumulative.  The Borrower  agrees that the rights of the
Banks and the  Administrative  Agent, or any of them, under this Agreement,  the
Loan  Agreement,  any other Loan Document or any other contract or agreement now
or hereafter in existence among the Banks and the  Administrative  Agent and the
Borrower or any Subsidiary of the Borrower and the other obligors thereunder, or
any of them,  shall be cumulative,  and that the  Administrative  Agent and each
Bank may from time to time exercise such rights and such remedies as such Person
or Persons may have  thereunder  and under the laws of the United  States or any
state, as applicable,  in the manner and at the time that such Person or Persons
in its or their sole discretion desire, subject to the terms of such agreements.
The  Borrower  further  expressly  agrees that the Banks and the  Administrative
Agent  shall in no event be under any  obligation  to  resort to any  Collateral
secured  hereby  prior to  exercising  any other  rights  that the Banks and the
Administrative  Agent,  or any of them,  may have  against  the  Borrower or any
Subsidiary of the Borrower or any of their respective properties,  nor shall the
Banks and the Administrative  Agent, or any of them, be obliged to resort to any
other  collateral or security for the  Obligations,  other than the  Collateral,
prior to any exercise of the Administrative  Agent's rights against the Borrower
and its property hereunder.

         16. Obligations  Commercial in Nature. The Borrower hereby acknowledges
that the Obligations arose out of a commercial  transaction,  and agrees that if
an Event of Default  shall occur and be  continuing,  the  Administrative  Agent
shall,  to the extent  permitted by Applicable  Law, have the right to immediate
possession  without notice or a hearing,  and hereby knowingly and intelligently
waives,  to the extent  permitted by  Applicable  Law, any and all rights it may
have to any  notice and  posting  of a bond by the Banks and the  Administrative
Agent, or any of them,  prior to seizure by the  Administrative  Agent or any of
its  transferees,  assigns or successors in interest,  of the  Collateral or any
portion thereof.

         17.  Amendments  and  Waivers.  No  amendment,   modification,  waiver,
transfer or renewal,  extension,  assignment or termination of this Agreement or
of the Loan  Agreement or of any other Loan  Document,  or of any  instrument or
document  executed and  delivered  by the  Borrower or any other  obligor to the
Banks and the Administrative Agent, or any of them, nor additional advances made
by the Banks and the Administrative Agent, or any of them, to the Borrower,  nor
the taking of further  security,  nor the retaking or  re-delivery or release of
the Collateral to the Borrower or any other  collateral or guaranty by the Banks
and the  Administrative  Agent,  or any of  them,  nor any lack of  validity  or
enforceability of any Loan Document or any term thereof nor any


                                       -9-


<PAGE>



other act of the  Banks  and the  Administrative  Agent,  or any of them,  shall
release the Borrower from any Obligation, except a release or discharge executed
in writing by the  Administrative  Agent in accordance  with the Loan  Agreement
with respect to such  Obligation  or upon full payment and  satisfaction  of all
Obligations and termination of the Commitment.  Neither the Administrative Agent
nor any Bank shall by any act, delay,  omission or otherwise,  be deemed to have
waived any of its or their rights or remedies  hereunder,  unless such waiver is
in writing and signed by the Administrative Agent or one or more of the Banks in
accordance  with the Loan  Agreement  and then only to the  extent  therein  set
forth. A waiver by the Banks and the  Administrative  Agent,  or any of them, of
any right or  remedy on any  occasion  shall  not be  construed  as a bar to the
exercise of any such right or remedy which any such Person would  otherwise have
had on any other occasion.

         18.  Assignment.  The Borrower hereby agrees that this Agreement or the
rights  hereunder  may, in the  discretion  of the Banks and the  Administrative
Agent  or any of  them,  as  applicable,  be  assigned  in  whole  or in part in
connection with any assignment of the Loan Agreement or the Obligations  arising
thereunder,  as permitted thereunder.  In the event this Agreement or the rights
hereunder are so assigned by any of the Banks and the Administrative  Agent, the
terms "Banks",  or "Administrative  Agent" wherever used herein shall be deemed,
as applicable, to refer to and include any such assignee.

         19. Successors and Assigns.  This Agreement shall apply to and bind the
respective  successors  and  permitted  assigns of the Borrower and inure to the
benefit of the successors and permitted  assigns of the Borrower,  the Banks and
the Administrative Agent.

         20. Notices. All notices and other communications required or permitted
hereunder  shall be in writing  and shall be given in the manner  prescribed  in
Section 11.1 of the Loan Agreement.

         21.  Governing Law. The provisions of this Agreement shall be construed
and  interpreted,   and  all  rights  and  obligations  of  the  parties  hereto
determined,  in  accordance  with  the  internal  laws of the  State of New York
applicable to contracts made and to be performed in the State of New York.  This
Agreement,  together  with all  documents  referred to herein,  constitutes  the
entire agreement among the Borrower and the Banks and the  Administrative  Agent
with respect to the matters addressed herein and may not be modified except by a
writing executed by the Administrative Agent and delivered to the Borrower.

         22.  Severability.  If any paragraph or part thereof of this  Agreement
shall for any reason be held or adjudged to be invalid, illegal or unenforceable
by any court of  competent  jurisdiction,  such  paragraph  or part  thereof  so
adjudicated invalid, illegal or unenforceable shall be deemed separate, distinct
and independent,


                                      -10-


<PAGE>



and the  remainder of this  Agreement  shall remain in full force and effect and
shall not be affected by such holding or adjudication.

         23. FCC Consent. Notwithstanding anything herein which may be construed
to the  contrary,  no action  shall be taken by the  Administrative  Agent  with
respect to the Licenses  issued by the FCC unless and until all  requirements of
Applicable Law, including,  without limitation,  any required approval under the
Communications Act, including without limitation the provision for ten (10) days
notice to the FCC required by 47 C.F.R. ss. 22.917(e),  requiring the consent to
or approval of such action by the FCC or any  governmental  or other  authority,
have  been  satisfied.   The  Borrower   covenants  that  upon  request  of  the
Administrative  Agent it will cause to be filed such  applications and take such
other  action as may be  reasonably  requested  by the  Administrative  Agent to
obtain the consent or approval of the FCC or any governmental or other authority
which has granted any License to the Borrower to any action contemplated by this
Agreement  and to give effect to the  Security  Interest  of the  Administrative
Agent,  including,  without  limitation,  the  execution of an  application  for
consent by the FCC to an assignment or transfer  involving a change in ownership
or control pursuant to the provisions of the Communications Act.

         24.  Counterparts.  This  Agreement  may be  executed  in any number of
counterparts,  each of which  shall be  deemed to be an  original,  but all such
separate counterparts shall together constitute but one and the same instrument.

         25.  Changes in Applicable  Law. The parties  acknowledge  their intent
that,  upon the occurrence and during the  continuation  of an Event of Default,
the  Administrative  Agent shall  receive,  to the fullest  extent  permitted by
Applicable Law and  governmental  policy  (including,  without  limitation,  the
rules,  regulations and policies of the FCC), all rights  necessary or desirable
to obtain,  use or sell the Collateral and to exercise all remedies available to
it under this Agreement, the UCC as in effect in any applicable jurisdiction, or
other  Applicable  Law. The parties  further  acknowledge and agree that, in the
event of changes in law or governmental policy occurring  subsequent to the date
hereof that affect in any manner the Administrative Agent's rights of access to,
or use or sale of, the  Collateral,  or the  procedures  necessary to enable the
Administrative  Agent  to  obtain  such  rights  of  access,  use or  sale,  the
Administrative  Agent and the Borrower shall amend this Agreement in such manner
as the  Administrative  Agent shall  reasonably  request in order to provide the
Administrative Agent such rights to the greatest extent possible consistent with
Applicable Law and governmental policy.



                                      -11-


<PAGE>



         26.  Administrative  Agent.  Each reference herein to any right granted
to, benefit  conferred upon or power exercisable by the  "Administrative  Agent"
shall be a  reference  to the  Administrative  Agent for the  benefit of all the
Banks,  and each action taken or right  exercised  hereunder  shall be deemed to
have been so taken or exercised by the  Administrative  Agent for the benefit of
and on behalf of all the Banks.

                  [Remainder of Page Intentionally Left Blank]


                                      -12-


<PAGE>



         IN WITNESS  WHEREOF,  the undersigned  have hereunto set their hands by
and through their duly authorized representatives,  as of the day and year first
written above.


BORROWER:                                    AMERICAN TOWER SYSTEMS, INC., a
                                             Delaware corporation



                                             By:
                                                      Its:

[CORPORATE SEAL]                             Attest:
                                                      Its:


ADMINISTRATIVE AGENT:                        TORONTO DOMINION (TEXAS), INC., as
                                             Administrative Agent


                                             By:
                                                      Its:



EXHIBITS

  Exhibit A  -  Contracts
  Exhibit B  -  Leases
  Exhibit C  -  Licenses


SCHEDULES

  Schedule 1  -  List and Location of Inventory
                             and Equipment


BORROWER'S SECURITY AGREEMENT
SIGNATURE PAGE 1

<PAGE>


                                    EXHIBIT C

                   FORM OF CERTIFICATE OF FINANCIAL CONDITION


         American Tower Systems,  Inc., a Delaware corporation (the "Borrower"),
in connection  with that certain Loan Agreement  (the "Loan  Agreement") of even
date herewith among the Borrower,  the Banks (as defined in the Loan  Agreement)
and Toronto Dominion (Texas),  Inc., as  administrative  agent for the Banks (in
such capacity,  the  "Administrative  Agent"),  pursuant to which the Banks have
agreed to make loans to the Borrower (the "Loans") as evidenced by those certain
promissory  notes of even  date  herewith  by the  Borrower  to the order of the
Banks, hereby certifies to each of the foregoing Persons other than the Borrower
that:


         1. The financial  statements  and all other  documents  relating to the
Borrower's  present or  projected  future  financial  condition  (together  with
similar  information  relating to the Restricted  Subsidiaries  of the Borrower)
provided to the  Administrative  Agent and the Banks in connection with the Loan
Agreement, have been prepared by the undersigned or under the supervision of the
undersigned,  with due  diligence  and in full  awareness of the reliance of the
Banks on the  information  contained  therein in reaching their decision to make
the Loans.  Such  financial  statements  (other than those relating to projected
financial condition) have been prepared in accordance with GAAP.

         2. The Borrower,  as a result of the Loans and any obligations incurred
in connection  therewith  and the other  transactions  contemplated  by the Loan
Agreement,  believes that the Borrower has not incurred and will not incur debts
beyond  its  ability to satisfy  them as they  mature,  and will have a positive
operating cash flow after paying all of its anticipated  indebtedness  when due,
including the obligations due to the Banks under the Loan Agreement.

         3. After  giving  effect to the Loans and the  obligations  incurred in
connection  therewith  and  the  other  transactions  contemplated  by the  Loan
Agreement and the Loan Documents, the Borrower (on a consolidated basis with its
Restricted Subsidiaries)  anticipates that it will have sufficient proceeds from
its cash  flow,  the sale of assets in the  ordinary  course  of  business,  the
proceeds  of  contemplated  sales of assets  not  necessary  for the  Borrower's
business (and the business of its Restricted  Subsidiaries),  and future debt or
equity  financings  sufficient  to  pay  cash  interest  expense  and  long-term
Indebtedness when due, whether at maturity or otherwise.




<PAGE>


         4. Immediately after giving effect to the transactions  contemplated by
the Loan Agreement and the other Loan Documents,  the fair saleable value of the
assets of the Borrower and its Restricted Subsidiaries (on a consolidated basis)
will exceed the aggregate  amount of all  Indebtedness  then  outstanding of the
Borrower and its Restricted Subsidiaries (on a consolidated basis).

         5.  Based on the  present  and  anticipated  needs for  capital  of the
businesses  conducted,  or  anticipated  to be  conducted  in the  future by the
Borrower and its Restricted Subsidiaries,  and after giving effect to the Loans,
the Borrower (on a consolidated basis with its Restricted Subsidiaries) will not
be left with  unreasonably  small  capital to finance the needs and  anticipated
needs of such businesses.

         Capitalized  terms used  herein and not  otherwise  defined are used as
defined in the Loan Agreement.


         IN WITNESS  WHEREOF,  the  Borrower  has caused the  execution  of this
Certificate and the affixation  hereto of the seal of the Borrower this ____ day
of November 1996.


                                             AMERICAN TOWER SYSTEMS, INC., a
                                             Delaware corporation



                                             By:

                                                      Its:
[CORPORATE SEAL]
                                             Attest:

                                                      Its:




                                       -2-


<PAGE>


                                    EXHIBIT D


                             FORM OF PROMISSORY NOTE


$____________________                                As of __________ ____, ____


         FOR VALUE RECEIVED,  the undersigned,  AMERICAN TOWER SYSTEMS,  INC., a
Delaware  corporation  (the  "Borrower"),  promises  to  pay  to  the  order  of
____________________  (hereinafter,  together with its  successors  and assigns,
called  the  "Bank"),  in  immediately  available  funds,  at such  place  as is
designated in or pursuant to the Loan Agreement (as  hereinafter  defined),  the
principal sum of ______________________ AND __/100s DOLLARS ($_________________)
of United States funds, or, if less, so much thereof as may from time to time be
advanced by the Bank to the Borrower and is outstanding hereunder, plus interest
as hereinafter  provided.  Such advances and repayments  thereof may be endorsed
from time to time on the grid  attached  hereto,  but the  failure  to make such
notations (or any error in such notation) shall not affect the obligation of the
Borrower to repay unpaid principal and interest hereunder.

         Except as otherwise  defined or limited herein,  capitalized terms used
herein shall have the meanings  ascribed to them in that certain Loan  Agreement
dated as of  ____________  ____,  1996 (as amended from time to time,  the "Loan
Agreement") among the Borrower, the Bank, the other financial institutions party
thereto  (together  with the Bank,  the "Banks") and Toronto  Dominion  (Texas),
Inc.,  as   administrative   agent  for  the  Banks  (in  such   capacity,   the
"Administrative Agent").

         The principal  amount of this Note shall be paid in such amounts and at
such times as are set forth in  Sections  2.5 and 2.7 of the Loan  Agreement.  A
final payment of all principal  amounts and other  Obligations  then outstanding
hereunder shall be due and payable in full on the Maturity Date.

         The Borrower shall be entitled to borrow,  repay and reborrow hereunder
pursuant to the terms and  conditions of the Loan  Agreement.  Prepayment of the
principal amount hereof may be made only as provided in the Loan Agreement.  The
principal amount of each Advance shall be repaid on its Payment Date.

         The Borrower  hereby  promises to pay interest on the unpaid  principal
amount of the Loans  outstanding  hereunder  as provided in the Loan  Agreement.
Interest  under  this Note shall  also be due and  payable  when this Note shall
become due  (whether  at  maturity,  by reason of  acceleration  or  otherwise).
Overdue


<PAGE>



principal  and, to the extent  permitted by Applicable  Law,  overdue  interest,
shall bear interest at the Default Rate as provided in the Loan Agreement.

         No  provision  of the Loan  Agreement  or this Note shall  require  the
payment or permit the  collection  of  interest in excess of that  permitted  by
Applicable  Law. If any excess  amount of  interest in such  respect is provided
for, or shall be adjudicated to be so provided for, in connection with the Loans
outstanding  hereunder,  the  provisions  of this  paragraph  shall  govern  and
prevail,  and neither the Borrower nor any sureties,  guarantors,  successors or
assigns of the  Borrower  shall be  obligated  to pay the excess  amount of such
interest or any other excess sum paid for the use, forbearance,  or detention of
sums loaned  pursuant  hereto.  In the event the Borrower ever pays, or the Bank
ever  receives,  collects or applies as interest any such sum, such amount which
would be in excess of the maximum  amount  permitted by Applicable  Law shall be
applied as a payment in the  reduction  of the  principal,  unless the  Borrower
shall  notify the Bank in writing  that it elects to have such  excess  returned
forthwith;  and, if the  principal has been paid in full,  any remaining  excess
shall  forthwith be returned to the Borrower.  Because of the variable nature of
the rates of interest  applicable to the Loans evidenced by this Note, the total
interest that will accrue  hereon  cannot be determined in advance.  Neither the
Borrower  nor the Bank intends for the Bank to contract  for,  charge or receive
usurious  interest and, to prevent such an occurrence,  any agreements which may
now or hereafter be in effect  between the Borrower and the Bank  regarding  the
payment  of fees to the  Bank  are  hereby  limited  by the  provisions  of this
paragraph.  To the extent not prohibited by Applicable Law, determination of the
legal  maximum  amount of  interest  shall at all  times be made by  amortizing,
prorating or  allocating  all interest at any time  contracted  for,  charged or
received  from  the  Borrower  in  connection  with  the  portion  of the  Loans
outstanding  hereunder  until the  Maturity  Date,  so that the  actual  rate of
interest  on  account  of the Loans  outstanding  hereunder  does not exceed the
maximum amount permitted under Applicable Law.

         All parties now or hereafter liable with respect to this Note,  whether
the Borrower,  any guarantor,  endorser or any other Person, hereby waive to the
extent  permitted by Applicable Law presentment for payment,  demand,  notice of
nonpayment or dishonor, protest and notice of protest.

         No delay or  omission  on the part of the Bank or any holder  hereof in
exercising  its rights under this Note,  or delay or omission on the part of the
Bank, the Administrative  Agent or the Banks collectively,  in exercising its or
their rights under the Loan Agreement or any other Loan Documents,  or course of
conduct relating thereto, shall operate as a waiver of such right or any


                                       -2-

<PAGE>



other right of the Bank or any holder hereof,  nor shall any waiver by the Bank,
the Administrative Agent or the Banks collectively, or any holder hereof, of any
such right or rights on any one  occasion  be deemed a bar to, or waiver of, the
same right or rights on any future occasion.

         The  Borrower  promises  to pay all  reasonable  costs  of  collection,
including  attorneys'  fees,  should  this Note be  collected  by or  through an
attorney-at-law or under advice therefrom.

         Time is of the essence of this Note.

         This Note  evidences  the  Bank's  portion of the Loans  under,  and is
entitled to the benefits and subject to the terms of, the Loan  Agreement  which
contains  provisions  with respect of the  acceleration  of the maturity of this
Note upon the happening of certain stated events and provisions for  prepayment.
This Note is secured by and is also  entitled to the  benefits  of the  Security
Documents.

         This Note shall be  construed  in  accordance  with and governed by the
internal laws of the State of New York  applicable  to contracts  made and to be
performed in the State of New York.




                  [Remainder of Page Intentionally Left Blank]


                                       -3-

<PAGE>



         IN WITNESS  WHEREOF,  the Borrower has executed this Note as of the day
and year first above written.


                                        AMERICAN TOWER SYSTEMS, INC., a Delaware
                                        corporation



                                        By:

                                            Its:

[CORPORATE SEAL]
                                        Attest:

                                            Its:


                                       -4-

<PAGE>


                                    ADVANCES




          Amount of          Amount of Principal                   Notation
Date       Advance             Paid or Prepaid                      Made By





















<PAGE>


                                    EXHIBIT E

                         FORM OF PARENT PLEDGE AGREEMENT



         THIS PARENT PLEDGE  AGREEMENT  (this  "Agreement"),  entered into as of
this 22th day of November 1996, by and between  American  Tower Systems  Holding
Corporation,  a Delaware  corporation  (the  "Pledgor"),  and  Toronto  Dominion
(Texas), Inc., as administrative agent (the "Administrative Agent") for itself
and on behalf of the Banks.


                              W I T N E S S E T H:


         WHEREAS,  American Tower  Systems,  Inc., a Delaware  corporation  (the
"Borrower"),  the Banks and the  Administrative  Agent are all  parties  to that
certain Loan  Agreement  dated as of even date herewith (the "Loan  Agreement");
and

         WHEREAS,  the Pledgor is the sole  stockholder  of the Borrower and, as
such,  will derive  substantial  direct and indirect  economic  benefit from the
making of the Loans; and

         WHEREAS,  as a condition  precedent  to the  effectiveness  of the Loan
Agreement, the Pledgor is required to execute and deliver this Agreement; and

         WHEREAS,  to secure the payment  and  performance  of Borrower  arising
under the Loan Agreement, the Pledgor and the Administrative Agent (on behalf of
itself and the Banks) have agreed that the shares of capital stock (the "Stock")
owned by the  Pledgor  in each of the  Subsidiaries  of the  Pledgor  listed  on
Schedule 1 attached hereto (the "Subsidiaries")  shall be pledged by the Pledgor
to the  Administrative  Agent (on  behalf of itself and the Banks) to secure the
Obligations (as defined below);

         NOW,  THEREFORE,  in  consideration of the foregoing and other good and
valuable  consideration,  the  receipt  and  sufficiency  of  which  are  hereby
acknowledged,  the parties hereto agree that capitalized terms used herein shall
have the  meanings  ascribed  to them in the Loan  Agreement  to the  extent not
otherwise defined or limited herein, and further agree as follows:

         1.  Warranty.  The  Pledgor  hereby  represents  and  warrants  to  the
Administrative  Agent and the  Banks  that,  except  for the  security  interest
created hereby,  the Pledgor owns the Stock, which constitutes the percentage of
the issued and outstanding  stock of the Subsidiaries as set forth on Schedule 1
attached hereto, free and clear of all Liens, that the Stock is duly


<PAGE>



issued, fully paid and non-assessable, and that the Pledgor has the unencumbered
right to pledge the Stock.  In addition,  Pledgor  represents  and  covenants as
follows:  (1) the Stock  represents all of Pledgor's  shares of capital stock in
any  Subsidiary;  (2)  upon  possession  and  retention  of  the  Stock  by  the
Administrative  Agent, the Administrative Agent shall have a valid and perfected
first  priority  security  interest  in the Stock,  securing  the payment of the
Obligations;  and (3) except as noted on Schedule 2 attached  hereto,  the Stock
represents all the  outstanding  shares of stock issued by any Subsidiary of the
Pledgor.

         2. Security  Interest.  Subject to the provisions of Section 13 hereof,
the Pledgor  hereby  unconditionally  grants and  assigns to the  Administrative
Agent, for itself and on behalf of the Banks,  and their  respective  successors
and assigns,  a continuing  security interest in and security title to the Stock
and any other shares of capital stock of any Subsidiary of the Pledgor  obtained
in the future, and in each case, all certificates  representing such shares, all
rights, options, warrants, stock or other securities or other property which may
hereafter  be  received,  receivable  or  distributed  in  respect of the Stock,
together with all proceeds of the foregoing,  including, without limitation, all
dividends, cash, notes, securities or other property from time to time acquired,
receivable  or  otherwise  distributed  in respect of, or in exchange  for,  the
foregoing,  all of which shall  constitute  "Stock"  hereunder.  The Pledgor has
delivered to and deposited  with the  Administrative  Agent  herewith all of its
right,  title and  interest  in and to the  Stock,  together  with  certificates
representing  the Stock, and undated stock powers endorsed in blank, as security
for the payment and performance of all of the obligations of the Pledgor and any
other obligor to the Administrative Agent, the Banks, or any of them, under this
Agreement and any  extensions,  renewals or amendments of any of the  foregoing,
however  created,  acquired,  arising or evidenced,  whether direct or indirect,
absolute or contingent,  now or hereafter existing, or due or to become due (the
"Obligations");  it being the  intention of the parties  hereto that  beneficial
ownership of the Stock, including,  without limitation,  all voting,  consensual
and dividend rights, shall remain in the Pledgor until the occurrence and during
continuance  of an Event of Default  and until the  Administrative  Agent  shall
notify the Pledgor of the Administrative Agent's exercise of voting and dividend
rights to the Stock pursuant to Section 9 of this Agreement.

         3.       Additional Shares.  In the event that, during the term
of this Agreement:

                  (a)      any stock dividend, stock split, reclassification,
         readjustment, or other change is declared or made in the

                                      - 2 -


<PAGE>



         capital structure of any Subsidiary, or any new stock is issued by such
         Subsidiary, all new, substituted, and additional shares shall be issued
         to the Pledgor and shall be promptly  delivered  to the  Administrative
         Agent,  together  with undated  stock  powers  endorsed in blank by the
         Pledgor,  and  shall  thereupon  constitute  Stock  to be  held  by the
         Administrative Agent under the terms of this Agreement; and

                  (b) any subscriptions, warrants or any other rights or options
         shall be issued in  connection  with the Stock,  all new stock or other
         securities  acquired through such  subscriptions,  warrants,  rights or
         options  by  the   Pledgor   shall  be   promptly   delivered   to  the
         Administrative  Agent,  together with undated Stock powers  endorsed in
         blank,  and  shall  thereupon  constitute  Stock  to  be  held  by  the
         Administrative Agent under the terms of this Agreement.

         4. Default.  In the event of the  occurrence of an Event of Default and
so long as any such Event of Default is continuing, subject, however, to Section
13 hereof, the  Administrative  Agent may sell or otherwise dispose of the Stock
at a public or private sale or make other commercially reasonable disposition of
the Stock or any portion  thereof after fifteen (15) days' notice to the Pledgor
and the  Administrative  Agent and the Banks,  or any of them,  may purchase the
Stock or any portion  thereof at any public sale.  The proceeds of the public or
private  sale or other  disposition  shall be applied  first to the costs of the
Administrative  Agent incurred in connection with the sale, expressly including,
without  limitation,  any costs under Section 7 hereof,  and then as provided in
the Loan Agreement.  In the event the proceeds of the sale or other  disposition
of the Stock are  insufficient  to satisfy the  Obligations,  the Pledgor  shall
remain liable for any such deficiency.  Pledgor waives,  to the extent permitted
by  Applicable  Law, the rights of equity of  redemption,  appraisal,  notice of
acceptance, presentment, demand and marshalling, to the extent applicable.

         5.  Additional  Rights of Secured Party.  In addition to its rights and
privileges under this Agreement,  the Administrative  Agent, on behalf of itself
and the Banks,  shall have all the rights,  powers and  privileges  of a secured
party  under  the  Uniform  Commercial  Code  as in  effect  in  any  applicable
jurisdiction and other Applicable Law.

         6.  Return  of  Stock  to the  Pledgor.  Upon  payment  in  full of all
principal  and interest on the Notes,  full  performance  by the Borrower of all
covenants,  undertakings and obligations  under the Loan Agreement and the other
Loan Documents,  and satisfaction in full of any other  Obligations,  other than
the Obligations  which survive the termination of the Loan Agreement as provided
in Section 11.16 of the Loan  Agreement,  and after such time as the Banks shall
have no obligation to make any further Advances

                                      - 3 -


<PAGE>



to the Borrower,  this Agreement  shall terminate and the  Administrative  Agent
shall return the remaining Stock and all rights  received by the  Administrative
Agent as a result of its possessory interest in the Stock to the Pledgor.

         7.  Disposition  of Stock by  Administrative  Agent.  The  Stock is not
registered or qualified  under the various  Federal or state  securities laws of
the  United  States and  disposition  thereof  after an Event of Default  may be
restricted to one or more private  (instead of public) sales in view of the lack
of such registration.  The Pledgor  understands that upon such disposition,  the
Administrative  Agent  may  approach  only  a  restricted  number  of  potential
purchasers  and further  understands  that a sale under such  circumstances  may
yield a lower  price  for  the  Stock  than if the  Stock  were  registered  and
qualified  pursuant  to Federal and state  securities  laws and sold on the open
market. The Pledgor, therefore, agrees that:

                  (a) if the Administrative  Agent shall,  pursuant to the terms
         of this Agreement, sell or cause the Stock or any portion thereof to be
         sold at a private sale, the  Administrative  Agent shall have the right
         to rely upon the  advice  and  opinion  of any  national  brokerage  or
         investment   firm  having   recognized   expertise  and  experience  in
         connection with shares of communications tower companies (but shall not
         be  obligated to seek such advice and the failure to do so shall not be
         considered in determining the commercial reasonableness of such action)
         as to the best  manner in which to expose  the Stock for sale and as to
         the best price reasonably obtainable at the private sale thereof; and

                  (b) that such reliance  shall be conclusive  evidence that the
         Administrative  Agent has handled such  disposition  in a  commercially
         reasonable manner absent manifest error.

         8. Pledgor's Obligations Absolute. The obligations of the Pledgor under
this Agreement  shall be direct and immediate and not  conditional or contingent
upon the pursuit of any remedies  against the Borrower or any other Person,  nor
against other  security or liens  available to the  Administrative  Agent or any
Bank.  The Pledgor  hereby waives any right to require that an action be brought
against any other  Person or to require that resort be had to any security or to
any balance of any deposit account or credit on the books of the  Administrative
Agent or any of the Banks in favor of any other  Person prior to the exercise of
remedies  hereunder,  or to  require  action  hereunder  prior to  resort by the
Administrative Agent to any other security or collateral for the Obligations. No
amendment,  modification,  waiver, transfer or renewal, extension, assignment or
termination  of this  Agreement  or of the Loan  Agreement  or of any other Loan
Document, or of any instrument or document executed and delivered

                                      - 4 -


<PAGE>



by the Pledgor or any other obligor with respect to the Obligations to the Banks
and the  Administrative  Agent, or any of them, nor additional  advances made by
the Banks and the Administrative Agent, or any of them, to the Borrower, nor the
taking of further  security,  nor the retaking or  re-delivery or release of the
Collateral  to the  Borrower  or any other  Person or any  other  collateral  or
guaranty to the Borrower or any other Person by the Banks and the Administrative
Agent,  or any of them, nor any lack of validity or  enforceability  of any Loan
Document  or  any  term  thereof,  nor  any  other  act  of the  Banks  and  the
Administrative  Agent,  or any of  them,  shall  release  the  Pledgor  from any
Obligation,   except  a  release  or  discharge   executed  in  writing  by  the
Administrative  Agent in accordance with the Loan Agreement with respect to such
Obligation or upon full payment and satisfaction of all Obligations. Neither the
Administrative  Agent  nor any  Bank  shall,  by any  act,  delay,  omission  or
otherwise,  be  deemed to have  waived  any of its or their  rights or  remedies
hereunder,  unless such  waiver is in writing  and signed by the  Administrative
Agent in accordance  with the Loan Agreement and then only to the extent therein
set forth. A waiver by the Banks and the  Administrative  Agent, or any of them,
of any right or remedy on any  occasion  shall not be  construed as a bar to the
exercise of any such right or remedy which any such Person would  otherwise have
had on any other occasion.

         9.       Voting Rights.

                  (a) For so long as any  Obligations  remain unpaid,  after and
         during the  continuation  of an Event of  Default,  but  subject to the
         provisions of Section 13 hereof, (i) the Administrative Agent may, upon
         fifteen (15) days' prior written notice to the Pledgor of its intention
         to do so,  exercise  all  voting  rights,  and all other  ownership  or
         consensual  rights  of the  Stock,  but under no  circumstances  is the
         Administrative  Agent  obligated  by the  terms  of this  Agreement  to
         exercise  such  rights,  and  (ii)  the  Pledgor  hereby  appoints  the
         Administrative  Agent,  which  appointment  shall be  effective  on the
         fifteenth   (15th)   day   following   the  giving  of  notice  by  the
         Administrative  Agent as provided in the foregoing Section 9(a)(i), the
         Pledgor's true and lawful  attorney-in-fact  and  IRREVOCABLE  PROXY to
         vote the Stock in any manner the  Administrative  Agent deems advisable
         for or against all matters  submitted  or which may be  submitted  to a
         vote of shareholders.  The power-of-attorney  granted hereby is coupled
         with an interest and shall be irrevocable.

                  (b) For so long as the  Pledgor  shall  have the right to vote
         the Stock,  the Pledgor  covenants and agrees that it will not, without
         the prior written consent of the Administrative Agent, vote or take any
         consensual  action with respect to the Stock which would  constitute an
         Event of Default.

                                      - 5 -


<PAGE>




         10. Notices. All notices and other communications required or permitted
hereunder  shall be in  writing,  and shall be given in the fashion set forth in
Section 11.1 of the Loan  Agreement,  and with  respect to the  Pledgor,  at the
address for the Borrower set forth in or otherwise  provided pursuant to Section
11.1 of the Loan Agreement.

         11.  Binding  Agreement.  The  provisions  of this  Agreement  shall be
construed and interpreted,  and all rights and obligations of the parties hereto
determined,  in  accordance  with  the  internal  laws of the  State of New York
applicable to contracts made and to be performed in the State of New York.  This
Agreement,  together  with all  documents  referred to herein,  constitutes  the
entire  agreement  between the  parties  with  respect to the matters  addressed
herein  and  may  not  be  modified   except  by  a  writing   executed  by  the
Administrative  Agent and the Pledgor and delivered by the Administrative  Agent
to the Pledgor.

         12. Severability. If any paragraph or part thereof shall for any reason
be held or  adjudged  to be invalid,  illegal or  unenforceable  by any court of
competent  jurisdiction,  such paragraph or part thereof so adjudicated invalid,
illegal or unenforceable shall be deemed separate, distinct and independent, and
the remainder of this Agreement  shall remain in full force and effect and shall
not be affected by such holding or adjudication.

         13.  FCC  Compliance.  Notwithstanding  anything  herein  which  may be
construed to the contrary,  no action shall be taken by the Administrative Agent
which may require the consent or approval of the FCC,  and the proxy  granted in
Section  9(a)  hereof  shall  not  become   effective,   unless  and  until  all
requirements of the Communications  Act, requiring the consent to or approval of
such  action  by the FCC  have  been  satisfied.  The  Pledgor  covenants  that,
following and during the continuance of an Event of Default, upon request of the
Administrative  Agent, it will cause to be filed such applications and take such
other  action as may be  reasonably  requested  by the  Administrative  Agent to
obtain  consent  or  approval  of the  FCC to any  action  contemplated  by this
Agreement  and to give effect to the  security  interest  of the  Administrative
Agent,  including,  without  limitation,  the  execution of an  application  for
consent by the FCC to an assignment or transfer  involving a change in ownership
or control pursuant to the provisions of the Communications Act.

         14.   Counterparts.   This   Agreement  may  be  executed  in  multiple
counterparts,  each of which  shall be  deemed to be an  original,  but all such
separate counterparts shall together constitute but one and the same instrument.

         15.  Administrative  Agent.  Each reference herein to any right granted
to, benefit conferred upon or power exercisable by

                                      - 6 -


<PAGE>



the "Administrative  Agent" shall be a reference to the Administrative Agent for
the benefit of all the Banks, and each action taken or right exercised hereunder
shall be deemed to have been so taken or exercised by the  Administrative  Agent
for the benefit of and on behalf of all the Banks.


                  [Remainder of Page Intentionally Left Blank]

                                      - 7 -


<PAGE>



         IN WITNESS WHEREOF,  the undersigned  parties hereto have executed this
Agreement by and through their duly authorized officers,  as of the day and year
first above written.


PLEDGOR:                                     AMERICAN TOWER SYSTEMS HOLDING
                                             CORPORATION, a Delaware corporation


                                             By:
         [CORPORATE SEAL]                             Title:

                                             Attest:
                                                      Title:



ADMINISTRATIVE AGENT:                        TORONTO DOMINION (TEXAS), INC., as
                                             Administrative Agent


                                             By:
                                                      Title:



Schedule 1 - Shares Pledged Pursuant to Pledge Agreement
Schedule 2 - Outstanding Shares of Stock








PARENT PLEDGE AGREEMENT
SIGNATURE PAGE 1

<PAGE>


                                    EXHIBIT F

                           FORM OF REQUEST FOR ADVANCE


         ______________________________,   the  duly   elected   and   qualified
____________________________   of  American  Tower  Systems,  Inc.,  a  Delaware
corporation (the "Borrower"), in connection with that certain Loan Agreement (as
in effect on the date hereof,  the "Loan  Agreement"),  dated as of November 22,
1996,  among the  Borrower,  the Banks (as  defined in the Loan  Agreement)  and
Toronto-Dominion  (Texas),  Inc., as administrative agent for the Banks (in such
capacity, the "Administrative Agent"), hereby certifies to each of the foregoing
Persons other than the Borrower that:

         1. The Borrower hereby requests an Advance in the amount of $__________
to be made on ____________ __, _____,  under the Commitment.  Such Advance shall
be a [Base Rate/LIBOR] Advance. [The Interest Period for the LIBOR Advance shall
be  _____________  month(s).] The proceeds of the Advance should be wired as set
forth on  Schedule  1  attached  hereto.  The  foregoing  instructions  shall be
irrevocable.

         2. All of the representations and warranties of the Borrower made under
the Loan Agreement  (including,  without  limitation,  all  representations  and
warranties  with  respect  to the  Borrower's  Subsidiaries)  and the other Loan
Documents are as of the date hereof, and will be as of the date of such Advance,
true and correct in all material  aspects both before and after giving effect to
the  application of the proceeds of the Advance of the Loans in connection  with
which this Request for Advance is given,  and after giving effect to any updates
to  information  provided to the Banks in accordance  with the terms of the Loan
Agreement.

         3.  There does not  exist,  as of this  date,  and there will not exist
after giving  effect to the Advance  requested in this Request for Advance,  any
Default under the Loan Agreement.

         4.       All Necessary Authorizations have been obtained or
made, are in full force and effect and are not subject to any
pending or threatened reversal or cancellation.

         5.       There has occurred no event having a Materially Adverse
Effect since ____________ ___, _____.





<PAGE>


         6. On the date of such  Advance,  after  giving  effect to the  Advance
requested hereby,  the Borrower shall be in compliance on a pro forma basis with
the covenants set forth in Sections 7.8, 7.9 and 7.10 of the Loan Agreement, and
Schedule  2  attached  hereto  sets  forth   calculations   demonstrating   such
compliance.

         7. All other conditions  precedent to the Advance  requested hereby set
forth in Section 3.2 of the Loan Agreement have been satisfied.

         Capitalized  terms used in this  Request for Advance and not  otherwise
defined are used as defined in the Loan Agreement.

         IN  WITNESS  WHEREOF,  the  Borrower,   acting  through  an  Authorized
Signatory,  has  signed  this  Request  for  Advance,  as of the  ______  day of
____________, 19__.


                                       AMERICAN TOWER SYSTEMS, INC., a Delaware
                                       corporation



                                       By:

                                                Its:







Schedule 1 - Wiring Instructions
Schedule 2 - Compliance Calculations


                                       -2-



<PAGE>


                                    EXHIBIT G

                           FORM OF SUBSIDIARY GUARANTY


         THIS SUBSIDIARY  GUARANTY (the  "Guaranty"),  made as of the ___ day of
__________, 19__, by ____________, a ___________ (the "Guarantor"),  in favor of
Toronto Dominion  (Texas),  Inc., as administrative  agent (the  "Administrative
Agent") for the Banks (as defined in the Loan Agreement described below).


                              W I T N E S S E T H:


         WHEREAS,  American  Tower  Systems  Inc., a Delaware  corporation  (the
"Borrower"),  the Banks,  and the  Administrative  Agent are all parties to that
certain Loan  Agreement  dated as of November 22, 1996 (as in effect on the date
hereof, the "Loan Agreement"); and

         WHEREAS, pursuant to the terms of the Loan Agreement, the
Guarantor is required to execute and deliver this Guaranty; and

         WHEREAS, the Guarantor is a Restricted Subsidiary of the
Borrower; and

         WHEREAS,  the Borrower and the Guarantor are mutually dependent on each
other in the conduct of their respective  businesses as an integrated operation,
and the Borrower has as one of its corporate purposes the obtaining of financing
needed from time to time by the Guarantor, with the Borrower's ability to obtain
such financing being dependent, in part, on the successful operations of and the
properties owned by the Guarantor; and

         WHEREAS, the Guarantor has determined that its execution,  delivery and
performance  of this  Guaranty  directly  benefit,  and are within the corporate
purposes and in the best interests of, the Guarantor; and

         WHEREAS, as a condition to the extension of the Loans by the Banks, the
Guarantor  has agreed to execute  this  Guaranty  guaranteeing  the  payment and
performance by the Borrower of its  obligations  and covenants  under the Notes,
the Loan Agreement and the other Loan Documents (the Loan  Agreement,  the Notes
and the other Loan Documents,  as executed on the date hereof and as they may be
amended, modified or extended from time to time being hereinafter referred to as
the "Guaranteed Agreements"); and




<PAGE>



         WHEREAS,  capitalized terms used herein and not otherwise defined shall
be used as defined in the Loan Agreement;

         NOW,  THEREFORE,  in consideration  of the above premises,  Ten Dollars
($10.00) in hand paid and other good and valuable consideration, the receipt and
sufficiency  of which are  hereby  acknowledged,  subject to the  provisions  of
Section 7 hereof, the Guarantor hereby  unconditionally  guarantees to the Banks
and the  Administrative  Agent full and prompt payment and performance  when due
whether at maturity,  by  acceleration  or otherwise  of all  Obligations.  Each
Obligation shall rank pari passu with each other Obligation.

         The Guarantor  hereby further agrees,  for the benefit of the Banks and
the Administrative Agent, that:

         1. Obligations Several. Regardless of whether any proposed guarantor or
any other Person or Persons is, are or shall become in any other way responsible
to the Banks and the Administrative  Agent, or any of them, for or in respect of
the Obligations or any part thereof, and regardless of whether or not any Person
or Persons  now or  hereafter  responsible  to the Banks and the  Administrative
Agent,  or any of them, for the  Obligations or any part thereof,  whether under
this Guaranty or otherwise,  shall cease to be so liable,  the Guarantor  hereby
declares  and agrees that this  Guaranty  is and shall  continue to be a several
obligation,  shall be a continuing  guaranty and shall be operative and binding,
and that the Guarantor  shall have no right of subrogation  with respect to this
Guaranty.

         2. Guaranty Final.  Upon the execution and delivery of this Guaranty to
the  Administrative  Agent, this Guaranty shall be deemed to be finally executed
and  delivered by the  Guarantor  and shall not be subject to or affected by any
promise or condition affecting or limiting the Guarantor's liability (other than
as expressly set forth in Section 7 hereof),  and no statement,  representation,
agreement or promise on the part of the Banks,  the  Administrative  Agent,  the
Borrower,  or any of them,  or any officer,  employee or agent  thereof,  unless
contained  herein  forms any part of this  Guaranty  or has  induced  the making
hereof  or  shall be  deemed  in any way to  affect  the  Guarantor's  liability
hereunder.

         3. Amendment and Waiver. No alteration or waiver of this Guaranty or of
any of its terms,  provisions  or  conditions  shall be binding upon the Persons
against  whom  enforcement  is sought  unless  made in writing  and signed by an
authorized officer of such Person.

         4. Dealings with Borrower.  The Banks and the Administrative  Agent, or
any of them,  may,  from time to time,  without  exonerating  or  releasing  the
Guarantor  in any way  under  this  Guaranty,  (i) take  such  further  or other
security or securities for the Obligations or any part thereof as the Banks

                                       -2-



<PAGE>



and the Administrative  Agent, or any of them, may deem proper,  consistent with
the Loan Agreement, or (ii) release,  discharge,  abandon or otherwise deal with
or fail to deal  with  any  guarantor  of the  Obligations  or any  security  or
securities  therefor or any part thereof now or hereafter  held by the Banks and
the  Administrative  Agent,  or any of them, or (iii)  consistent  with the Loan
Agreement,  amend, modify, extend,  accelerate or waive in any manner any of the
provisions,  terms, or conditions of the Guaranteed Agreements, all as the Banks
and  the  Administrative  Agent,  or any of  them,  may  consider  expedient  or
appropriate  in their sole  discretion.  Without  limiting the generality of the
foregoing,  or of Paragraph 5 hereof,  it is  understood  that the Banks and the
Administrative  Agent, or any of them, may, without exonerating or releasing the
Guarantor,  give up, or modify or abstain from perfecting or taking advantage of
any  security  for the  Obligations  and  accept  or make  any  compositions  or
arrangements,  and realize upon any security for the  Obligations  when,  and in
such manner, as the Banks and the Administrative Agent, or any of them, may deem
expedient,  consistent  with the  Loan  Agreement,  all  without  notice  to the
Guarantor, except as required by Applicable Law.

         5. Guaranty  Unconditional.  The Guarantor acknowledges and agrees that
no change in the  nature or terms of the  Obligations  or any of the  Guaranteed
Agreements, or other agreements, instruments or contracts evidencing, related to
or  attendant  with  the   Obligations   (including   any  novation),   nor  any
determination of lack of enforceability thereof, shall discharge all or any part
of the liabilities  and obligations of the Guarantor  pursuant to this Guaranty;
it  being  the  purpose  and  intent  of  the  Guarantor,   the  Banks  and  the
Administrative  Agent that the  covenants,  agreements and all  liabilities  and
obligations  of  the  Guarantor   hereunder  are  absolute,   unconditional  and
irrevocable under any and all circumstances.  Without limiting the generality of
the  foregoing,  the  Guarantor  agrees  that  until  each and  every one of the
covenants and agreements of this Guaranty is fully  performed,  the  Guarantor's
undertakings hereunder shall not be released, in whole or in part, by any action
or thing which might, but for this paragraph of this Guaranty, be deemed a legal
or  equitable  discharge of a surety or  guarantor,  or by reason of any waiver,
omission of the Banks and the  Administrative  Agent,  or any of them,  or their
failure to proceed  promptly or  otherwise,  or by reason of any action taken or
omitted by the Banks and the  Administrative  Agent, or any of them,  whether or
not such  action or failure to act varies or  increases  the risk of, or affects
the rights or remedies of, the  Guarantor  or by reason of any further  dealings
between the Borrower, the Banks and the Administrative Agent, or any of them, or
any other  guarantor or surety,  and the Guarantor,  to the extent  permitted by
Applicable  Law,  hereby  expressly  waives and  surrenders  any  defense to its
liability  hereunder,  or any right of  counterclaim  or offset of any nature or
description which it may have or which may exist based upon, and shall be deemed
to have consented to,

                                       -3-



<PAGE>



any of the foregoing acts, omissions, things, agreements or waivers.

         6. Set-off.  The Banks and the  Administrative  Agent,  or any of them,
may, without demand or notice of any kind upon or to the Guarantor,  at any time
or from time to time when any amount  shall be due and payable  hereunder by the
Guarantor,  if the Borrower shall not have timely paid its Obligations,  set off
and  appropriate  any  property,  balances,  credit  accounts  or  moneys of the
Guarantor  (other than those held in a trust) in the possession of the Banks and
the  Administrative  Agent,  or any of them, or under the control of any of them
for any  purpose,  which  property,  balances,  credit  accounts or moneys shall
thereupon be turned over and remitted to the  Administrative  Agent,  to be held
and applied to the  Obligations by the  Administrative  Agent in accordance with
the Loan  Agreement,  and the  Guarantor  hereby  grants  to the  Banks  and the
Administrative   Agent,  a  security   interest  in  all  such   property.   The
Administrative  Agent shall give written  notice to the Borrower of the exercise
of any of the  foregoing  rights  within  one (1)  Business  Day  following  the
exercise thereof.

         7. Maximum  Guaranteed  Amount.  The creation or existence from time to
time of Obligations  in excess of the amount  committed to or outstanding on the
date of this Guaranty is hereby  authorized by the Guarantor,  without notice to
the Guarantor,  and shall in no way impair or affect this Guaranty or the rights
of the Banks and the Administrative  Agent, or any of them, herein.  Anything in
this  Guaranty  to be  contrary  notwithstanding,  it is  the  intention  of the
Guarantor,  the  Banks  and  the  Administrative  Agent,  that  the  Guarantor's
obligations  hereunder  shall be, but not in excess of, the  Maximum  Guaranteed
Amount. The "Maximum Guaranteed Amount" shall mean the greater of (a) the amount
of economic benefit received  (directly or indirectly) by the Guarantor pursuant
to the Loan Agreement and the other Loan  Documents,  and (b) the maximum amount
which could be paid out by the Guarantor without rendering this Guaranty void or
voidable under Applicable Law including, without limitation, (i) Title 11 of the
United  States  Code,  as  amended,  and (ii)  applicable  state  law  regarding
fraudulent conveyances.

         8. Bankruptcy.  Upon the bankruptcy or winding up or other distribution
of assets of the  Borrower or any  Subsidiary  of the  Borrower  (other than the
Guarantor) or of any surety or guarantor for the Obligations,  the rights of the
Banks and the Administrative  Agent, or any of them, against the Guarantor shall
not be affected or impaired by the omission of the Banks and the  Administrative
Agent, or any of them, to prove its or their claim, as appropriate,  or to prove
its or their full claim,  as appropriate,  and the Banks and the  Administrative
Agent may prove such  claims as they see fit and may  refrain  from  proving any
claim  and in their  respective  discretion  they  may  value as they see fit or
refrain from valuing any security held by the Banks

                                       -4-



<PAGE>



and the  Administrative  Agent,  or any of them,  without in any way  releasing,
reducing  or   otherwise   affecting   the   liability  to  the  Banks  and  the
Administrative Agent of the Guarantor.

         9.  Application of Payments.  Any amount  received by the Banks and the
Administrative  Agent, or any of them, from whatsoever source and applied toward
the payment of the Obligations  shall be applied in such order of application as
is set forth in the Loan Agreement.

         10. Waivers by Guarantor. The Guarantor hereby expressly waives, to the
extent  permitted by Applicable  Law: (a) notice of acceptance of this Guaranty,
(b) notice of the  existence or creation of all or any of the  Obligations,  (c)
presentment,  demand,  notice  of  dishonor,  protest,  and  all  other  notices
whatsoever, (d) all diligence in collection or protection of or realization upon
the Obligations or any part thereof, any obligation  hereunder,  or any security
for any of the  foregoing  and (e) all rights of  subrogation,  indemnification,
contribution and reimbursement  against the Borrower,  all rights to enforce any
remedy the Banks and the Administrative  Agent, or any of them, may have against
the Borrower and any benefit of, or right to  participate  in, any collateral or
security now or hereinafter held by the Banks and the  Administrative  Agent, or
any of them,  in respect of the  Obligations,  even upon  payment in full of the
Obligations.  Any money  received by the  Guarantor in violation of this Section
shall be held in trust by the  Guarantor  for the  benefit  of the Banks and the
Administrative  Agent.  If  a  claim  is  ever  made  upon  the  Banks  and  the
Administrative  Agent,  or any of them,  for the  repayment  or  recovery of any
amount or amounts  received by any of them in payment of any of the  Obligations
and such Person repays all or part of such amount by reason of (a) any judgment,
decree,  or order of any court or administrative  body having  jurisdiction over
such  Person  or any of its  property,  or (b)  any  good  faith  settlement  or
compromise  of any such claim  effected by such  Person with any such  claimant,
including  the Borrower,  then in such event the Guarantor  agrees that any such
judgment,  decree,  order,  settlement,  or compromise shall be binding upon the
Guarantor,  notwithstanding  any revocation  hereof or the  cancellation  of any
promissory note or other instrument  evidencing any of the Obligations,  and the
Guarantor shall be and remain  obligated to such Person hereunder for the amount
so repaid or recovered to the same extent as if such amount had never originally
been received by such Person.

         11.  Assignment  by  Banks  or  Administrative  Agent.  To  the  extent
permitted under the Loan Agreement,  the Banks and the Administrative  Agent may
each, and without notice of any kind,  except as otherwise  required by the Loan
Agreement,  sell, assign or transfer all or any of the Obligations,  and in such
event each and every immediate and successive assignee, transferee, or holder of
all or any of the Obligations, shall have the right to enforce this Guaranty, by
suit or otherwise, for the benefit of

                                       -5-



<PAGE>



such assignee,  transferee or holder as fully as if such assignee, transferee or
holder were herein by name specifically given such rights, powers and benefits.

         12. Remedies  Cumulative.  No delay by the Banks and the Administrative
Agent, or any of them, in the exercise of any right or remedy shall operate as a
waiver  thereof,  and no  single  or  partial  exercise  by the  Banks  and  the
Administrative  Agent,  or any of them,  of any right or remedy  shall  preclude
other or further  exercise thereof or the exercise of any other right or remedy.
No action by the Banks and the Administrative  Agent, or any of them,  permitted
hereunder  shall in any way impair or affect this  Guaranty.  For the purpose of
this  Guaranty,   the  Obligations  shall  include,   without  limitation,   all
Obligations  of  the  Borrower  to  the  Banks  and  the  Administrative   Agent
notwithstanding  any right or power of any third party,  individually  or in the
name of the Borrower or any other  Person,  to assert any claim or defense as to
the invalidity or unenforceability of any such Obligation,  and no such claim or
defense shall impair or affect the obligations of the Guarantor hereunder.

         13.  Successors  and Assigns.  This Guaranty  shall be binding upon the
Guarantor, its successors and assigns and inure to the benefit of the successors
and  assigns  of the  Guarantor,  the Banks and the  Administrative  Agent.  The
Guarantor shall not assign its rights or obligations under this Guaranty without
the  consent  of the  Administrative  Agent  and all the  Banks,  nor  shall the
Guarantor amend this Guaranty,  without the consent of the Administrative  Agent
and the Majority Banks.

         14. Miscellaneous. This is a Guaranty of payment and not of collection.
In the event of a demand upon the Guarantor  under this Guaranty,  the Guarantor
shall be held and bound to the Banks and the  Administrative  Agent  directly as
debtor  in  respect  of  the  payment  of the  amounts  hereby  guaranteed.  All
reasonable costs and expenses,  including attorneys' fees and expenses, incurred
by the  Banks  and  the  Administrative  Agent,  or any of  them,  in  obtaining
performance  of or collecting  payments due under this Guaranty  shall be deemed
part of the Obligations  guaranteed hereby. Any notice or demand which the Banks
and the  Administrative  Agent, or any of them, may wish to give shall be served
upon the Guarantor in the fashion  prescribed for notices in Section 11.1 of the
Loan Agreement in care of the Borrower at the address for the Borrower set forth
in or otherwise provided pursuant to Section 11.1 of the Loan Agreement, and the
notice so sent shall be deemed to be served as set forth in Section  11.1 of the
Loan Agreement.

         15. Loans Benefit  Guarantor.  The Guarantor  expressly  represents and
acknowledges   that  any   financial   accommodations   by  the  Banks  and  the
Administrative  Agent,  or any of  them,  to the  Borrower,  including,  without
limitation the extension of the

                                       -6-



<PAGE>



Loans,  are  and  will be of  direct  interest,  benefit  and  advantage  to the
Guarantor.

         16. Solvency.  The Guarantor expressly  represents and warrants that as
of the date hereof and after giving effect to the  transactions  contemplated by
the Loan Documents (i) the property of the Guarantor, at a fair valuation,  will
exceed its debt;  (ii) the  capital of the  Guarantor  will not be  unreasonably
small to conduct its business; (iii) the Guarantor will not have incurred debts,
or have  intended to incur  debts,  beyond its ability to pay such debts as they
mature;  and (iv) the present fair salable  value of the assets of the Guarantor
will be  materially  greater  than the amount  that will be  required to pay its
probable liabilities  (including debts) as they become absolute and matured. For
purposes of this Section 16, "debt" means any liability on a claim,  and "claim"
means  (a) the  right to  payment,  whether  or not such  right  is  reduced  to
judgment,  liquidated,  unliquidated,  fixed,  contingent,  matured,  unmatured,
undisputed,  legal,  equitable,  secured  or  unsecured,  or (b) the right to an
equitable  remedy for breach of performance if such breach gives rise to a right
to  payment,  whether  or not such  right to an  equitable  remedy is reduced to
judgment,  fixed,  contingent,   matured,  unmatured,   undisputed,  secured  or
unsecured.

         17. Visits and Inspections.  The Guarantor covenants and agrees that so
long as any amount is owing on account of Obligations  or otherwise  pursuant to
this Guaranty,  the Guarantor shall permit  representatives of the Banks and the
Administrative  Agent,  or any of them,  to visit and inspect  properties of the
Guarantor  during normal  business hours after  reasonable  notice,  inspect the
Guarantor's  books and records and discuss  with the  principal  officers of the
Guarantor its businesses,  assets, liabilities,  financial positions, results of
operations and business prospects.

         18.  Governing Law. This Guaranty shall be construed in accordance with
and  governed  by the  internal  laws of the  State  of New York  applicable  to
contracts made and to be performed in the State of New York.

         19.  Jurisdiction  and  Venue.  If any  action or  proceeding  shall be
brought  by the  Administrative  Agent in order to  enforce  any right or remedy
under this Guaranty,  the Guarantor  hereby consents to the  jurisdiction of any
state or  federal  court  of  competent  jurisdiction  sitting  within  the area
comprising the Southern  District of New York on the date of this Guaranty.  The
Guarantor hereby agrees,  to the extent permitted by Applicable Law that service
of the summons and  complaint  and all other  process which may be served in any
such suit,  action or proceeding may be effected by mailing by registered mail a
copy  of such  process  to the  offices  of the  Borrower,  as set  forth  in or
otherwise  provided  pursuant to Section  11.1 of the Loan  Agreement,  and that
personal service of process shall not be

                                       -7-



<PAGE>



required.  Nothing  herein shall be construed to prohibit  service of process by
any other  method  permitted  by law,  or the  bringing  of any suit,  action or
proceeding in any other  jurisdiction.  The Guarantor agrees that final judgment
in such suit,  action or proceeding  shall be conclusive  and may be enforced in
any other  jurisdiction  by suit on the judgment or in any other manner provided
by Applicable Law.

         20. Waiver of Jury Trial.  The Guarantor waives any right to a trial by
jury in any proceeding arising out of this Guaranty.

         21.  Time of the  Essence.  Time is of the  essence  with regard to the
Guarantor's performance of its obligations hereunder.

         22.  Administrative  Agent.  Each reference herein to any right granted
to, benefit  conferred upon or power exercisable by the  "Administrative  Agent"
shall be a reference to the  Administrative  Agent for the benefit of itself and
all the Banks,  and each  action  taken or right  exercised  hereunder  shall be
deemed to have been so taken or  exercised by the  Administrative  Agent for the
benefit of and on behalf of itself and all the Banks.

         23.  Ratifications.  The  Guarantor  hereby  ratifies  and affirms each
representation, warranty, covenant and other agreement made on its behalf by the
Borrower in the Loan Agreement.



              [THE REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

                                       -8-



<PAGE>


         IN WITNESS  WHEREOF,  the  Guarantor  has caused  this  Guaranty  to be
executed and sealed as of the date first above written.


ADMINISTRATIVE AGENT:                         TORONTO DOMINION (TEXAS), INC., as
                                              Administrative Agent


                                              By:

                                                     Its:


GUARANTOR:                                    _______________, a _______________


                                              By:

                                                     Its:
[CORPORATE SEAL]

                                              Attest:

                                                     Its:




SUBSIDIARY GUARANTY
Signature Page 1


<PAGE>


                                    EXHIBIT H

                       FORM OF SUBSIDIARY PLEDGE AGREEMENT



         THIS SUBSIDIARY PLEDGE AGREEMENT (the "Agreement"),  entered into as of
this ___ day of October, 1996, by and between ___________________,  a __________
(the "Pledgor") and Toronto Dominion (Texas), Inc., as administrative agent (the
"Administrative Agent") for itself and on behalf of the Banks.


                              W I T N E S S E T H:


         WHEREAS,  American Tower  Systems,  Inc., a Delaware  corporation  (the
"Borrower"),  the Banks and the  Administrative  Agent are all  parties  to that
certain Loan  Agreement  dated as of November 22, 1996 (as in effect on the date
hereof, the "Loan Agreement"); and

         WHEREAS,  pursuant to the terms of the Loan  Agreement,  the Pledgor is
required to execute and deliver this Agreement; and

         WHEREAS, the Pledgor is a Restricted  Subsidiary of the Borrower and is
engaged in the business of owning and operating  communications tower facilities
as an integrated operation with the Borrower and its other Subsidiaries; and

         WHEREAS,  the Pledgor has determined  that its execution,  delivery and
performance of this  Agreement  directly  benefit,  and are within the corporate
purposes and in the best interests of, the Pledgor; and

         WHEREAS,  to secure the payment and performance of, among other things,
the obligations of the Pledgor arising from that certain Subsidiary  Guaranty of
even  date  herewith   (the   "Subsidiary   Guaranty"),   the  Pledgor  and  the
Administrative  Agent (on behalf of itself and the Banks)  have  agreed that the
shares of  capital  stock  (the  "Stock")  owned by the  Pledgor  in each of the
Subsidiaries   of  the  Pledgor  listed  on  Schedule  1  attached  hereto  (the
"Subsidiaries")  shall be pledged by the Pledgor to the Administrative Agent (on
behalf of itself and the Banks) to secure the Obligations (as defined below);

         NOW,  THEREFORE,  in  consideration of the foregoing and other good and
valuable  consideration,  the  receipt  and  sufficiency  of  which  are  hereby
acknowledged,  the parties hereto agree that capitalized terms used herein shall
have the  meanings  ascribed  to them in the Loan  Agreement  to the  extent not
otherwise defined or limited herein, and further agree as follows:



<PAGE>




         1.  Warranty.  The  Pledgor  hereby  represents  and  warrants  to  the
Administrative  Agent and the  Banks  that,  except  for the  security  interest
created hereby,  the Pledgor owns the Stock, which constitutes the percentage of
the issued and outstanding  stock of the Subsidiaries as set forth on Schedule 1
attached  hereto,  free and clear of all Liens,  that the Stock is duly  issued,
fully paid and  non-assessable,  and that the Pledgor has the unencumbered right
to pledge the Stock. In addition,  Pledgor  represents and covenants as follows:
(1) the  Stock  represents  all of  Pledgor's  shares  of  capital  stock in any
Subsidiary; (2) upon possession and retention of the Stock by the Administrative
Agent, the Administrative  Agent shall have a valid and perfected first priority
security interest in the Stock, securing the payment of the Obligations; and (3)
except as noted on  Schedule 2 attached  hereto,  the Stock  represents  all the
outstanding shares of stock issued by any Subsidiary of the Pledgor.

         2. Security  Interest.  Subject to the provisions of Section 13 hereof,
the Pledgor  hereby  unconditionally  grants and  assigns to the  Administrative
Agent, for itself and on behalf of the Banks,  and their  respective  successors
and assigns,  a continuing  security interest in and security title to the Stock
and any other shares of capital stock of any Subsidiary of the Pledgor  obtained
in the future, and in each case, all certificates  representing such shares, all
rights, options, warrants, stock or other securities or other property which may
hereafter  be  received,  receivable  or  distributed  in  respect of the Stock,
together with all proceeds of the foregoing,  including, without limitation, all
dividends, cash, notes, securities or other property from time to time acquired,
receivable  or  otherwise  distributed  in respect of, or in exchange  for,  the
foregoing,  all of which shall  constitute  "Stock"  hereunder.  The Pledgor has
delivered to and deposited  with the  Administrative  Agent  herewith all of its
right,  title and  interest  in and to the  Stock,  together  with  certificates
representing  the Stock, and undated stock powers endorsed in blank, as security
for the payment and performance of all of the obligations of the Pledgor and any
other obligor to the Administrative Agent, the Banks, or any of them, under this
Agreement and the Subsidiary Guaranty and any extensions, renewals or amendments
of any of the  foregoing,  however  created,  acquired,  arising  or  evidenced,
whether direct or indirect,  absolute or contingent,  now or hereafter existing,
or due or to  become  due (the  "Obligations");  it being the  intention  of the
parties  hereto  that  beneficial  ownership  of the Stock,  including,  without
limitation,  all voting,  consensual  and dividend  rights,  shall remain in the
Pledgor until the occurrence  and during  continuance of an Event of Default and
until the  Administrative  Agent shall notify the Pledgor of the  Administrative
Agent's  exercise of voting and dividend rights to the Stock pursuant to Section
9 of this Agreement.

                                      - 2 -


<PAGE>




         3.       Additional Shares.  In the event that, during the term
of this Agreement:

                  (a)  any  stock  dividend,   stock  split,   reclassification,
         readjustment,  or  other  change  is  declared  or made in the  capital
         structure  of any  Subsidiary,  or any  new  stock  is  issued  by such
         Subsidiary, all new, substituted, and additional shares shall be issued
         to the Pledgor and shall be promptly  delivered  to the  Administrative
         Agent,  together  with undated  stock  powers  endorsed in blank by the
         Pledgor,  and  shall  thereupon  constitute  Stock  to be  held  by the
         Administrative Agent under the terms of this Agreement; and

                  (b) any subscriptions, warrants or any other rights or options
         shall be issued in  connection  with the Stock,  all new stock or other
         securities  acquired through such  subscriptions,  warrants,  rights or
         options  by  the   Pledgor   shall  be   promptly   delivered   to  the
         Administrative  Agent,  together with undated Stock powers  endorsed in
         blank,  and  shall  thereupon  constitute  Stock  to  be  held  by  the
         Administrative Agent under the terms of this Agreement.

         4. Default.  In the event of the  occurrence of an Event of Default and
so long as any such Event of Default is continuing, subject, however, to Section
13 hereof, the  Administrative  Agent may sell or otherwise dispose of the Stock
at a public or private sale or make other commercially reasonable disposition of
the Stock or any portion  thereof after fifteen (15) days' notice to the Pledgor
and the  Administrative  Agent and the Banks,  or any of them,  may purchase the
Stock or any portion  thereof at any public sale.  The proceeds of the public or
private  sale or other  disposition  shall be applied  first to the costs of the
Administrative  Agent incurred in connection with the sale, expressly including,
without  limitation,  any costs under Section 7 hereof,  and then as provided in
the Loan Agreement.  In the event the proceeds of the sale or other  disposition
of the Stock are  insufficient  to satisfy the  Obligations,  the Pledgor  shall
remain liable for any such deficiency.  Pledgor waives,  to the extent permitted
by  Applicable  Law, the rights of equity of  redemption,  appraisal,  notice of
acceptance, presentment, demand and marshalling, to the extent applicable.

         5.  Additional  Rights of Secured Party.  In addition to its rights and
privileges under this Agreement,  the Administrative  Agent, on behalf of itself
and the Banks,  shall have all the rights,  powers and  privileges  of a secured
party  under  the  Uniform  Commercial  Code  as in  effect  in  any  applicable
jurisdiction and other Applicable Law.

         6.  Return  of  Stock  to the  Pledgor.  Upon  payment  in  full of all
principal  and interest on the Notes,  full  performance  by the Borrower of all
covenants, undertakings and obligations under

                                      - 3 -


<PAGE>



the Loan Agreement and the other Loan Documents, and satisfaction in full of any
other  Obligations,  other than the Obligations which survive the termination of
the Loan Agreement as provided in Section 11.16 of the Loan Agreement, and after
such time as the Banks shall have no obligation to make any further  Advances to
the Borrower,  this Agreement shall terminate and the Administrative Agent shall
return the remaining Stock and all rights received by the  Administrative  Agent
as a result of its possessory interest in the Stock to the Pledgor.

         7.  Disposition  of Stock by  Administrative  Agent.  The  Stock is not
registered or qualified  under the various  Federal or state  securities laws of
the  United  States and  disposition  thereof  after an Event of Default  may be
restricted to one or more private  (instead of public) sales in view of the lack
of such registration.  The Pledgor  understands that upon such disposition,  the
Administrative  Agent  may  approach  only  a  restricted  number  of  potential
purchasers  and further  understands  that a sale under such  circumstances  may
yield a lower  price  for  the  Stock  than if the  Stock  were  registered  and
qualified  pursuant  to Federal and state  securities  laws and sold on the open
market. The Pledgor, therefore, agrees that:

                  (a) if the Administrative  Agent shall,  pursuant to the terms
         of this Agreement, sell or cause the Stock or any portion thereof to be
         sold at a private sale, the  Administrative  Agent shall have the right
         to rely upon the  advice  and  opinion  of any  national  brokerage  or
         investment   firm  having   recognized   expertise  and  experience  in
         connection with shares of communications tower companies (but shall not
         be  obligated to seek such advice and the failure to do so shall not be
         considered in determining the commercial reasonableness of such action)
         as to the best  manner in which to expose  the Stock for sale and as to
         the best price reasonably obtainable at the private sale thereof; and

                  (b) that such reliance  shall be conclusive  evidence that the
         Administrative  Agent has handled such  disposition  in a  commercially
         reasonable manner absent manifest error.

         8. Pledgor's Obligations Absolute. The obligations of the Pledgor under
this Agreement  shall be direct and immediate and not  conditional or contingent
upon the pursuit of any remedies  against the Borrower or any other Person,  nor
against other  security or liens  available to the  Administrative  Agent or any
Bank.  The Pledgor  hereby waives any right to require that an action be brought
against any other  Person or to require that resort be had to any security or to
any balance of any deposit account or credit on the books of the  Administrative
Agent or any of the Banks in favor of any other  Person prior to the exercise of
remedies hereunder, or to require action hereunder prior to

                                      - 4 -


<PAGE>



resort by the  Administrative  Agent to any other security or collateral for the
Obligations. No amendment, modification, waiver, transfer or renewal, extension,
assignment or  termination  of this Agreement or of the Loan Agreement or of any
other Loan Document,  or of any instrument or document executed and delivered by
the Pledgor or any other  obligor with respect to the  Obligations  to the Banks
and the  Administrative  Agent, or any of them, nor additional  advances made by
the Banks and the Administrative Agent, or any of them, to the Borrower, nor the
taking of further  security,  nor the retaking or  re-delivery or release of the
Collateral  to the  Borrower  or any other  person or any  other  collateral  or
guaranty by the Banks and the Administrative Agent, or any of them, nor any lack
of validity or enforceability of any Loan Document or any term thereof,  nor any
other act of the  Banks  and the  Administrative  Agent,  or any of them,  shall
release the Pledgor from any Obligation,  except a release or discharge executed
in writing by the  Administrative  Agent in accordance  with the Loan  Agreement
with respect to such  Obligation  or upon full payment and  satisfaction  of all
Obligations.  Neither the  Administrative  Agent nor any Bank shall, by any act,
delay,  omission  or  otherwise,  be deemed to have  waived  any of its or their
rights or remedies hereunder, unless such waiver is in writing and signed by the
Administrative  Agent in accordance with the Loan Agreement and then only to the
extent therein set forth. A waiver by the Banks and the Administrative Agent, or
any of them, of any right or remedy on any occasion  shall not be construed as a
bar to the  exercise  of any such right or remedy  which any such  Person  would
otherwise have had on any other occasion.

         9.       Voting Rights.

                  (a) For so long as any  Obligations  remain unpaid,  after and
         during the  continuation  of an Event of  Default,  but  subject to the
         provisions of Section 13 hereof, (i) the Administrative Agent may, upon
         fifteen (15) days' prior written notice to the Pledgor of its intention
         to do so,  exercise  all  voting  rights,  and all other  ownership  or
         consensual  rights  of the  Stock,  but under no  circumstances  is the
         Administrative  Agent  obligated  by the  terms  of this  Agreement  to
         exercise  such  rights,  and  (ii)  the  Pledgor  hereby  appoints  the
         Administrative  Agent,  which  appointment  shall be  effective  on the
         fifteenth   (15th)   day   following   the  giving  of  notice  by  the
         Administrative  Agent as provided in the foregoing Section 9(a)(i), the
         Pledgor's true and lawful  attorney-in-fact  and  IRREVOCABLE  PROXY to
         vote the Stock in any manner the  Administrative  Agent deems advisable
         for or against all matters  submitted  or which may be  submitted  to a
         vote of shareholders.  The power-of-attorney  granted hereby is coupled
         with an interest and shall be irrevocable.


                                      - 5 -


<PAGE>



                  (b) For so long as the  Pledgor  shall  have the right to vote
         the Stock,  the Pledgor  covenants and agrees that it will not, without
         the prior written consent of the Administrative Agent, vote or take any
         consensual  action with respect to the Stock which would  constitute an
         Event of Default.

         10. Notices. All notices and other communications required or permitted
hereunder  shall be in  writing,  and shall be given in the fashion set forth in
Section 11.1 of the Loan  Agreement,  and with  respect to the  Pledgor,  at the
address for the Borrower set forth in or otherwise  provided pursuant to Section
11.1 of the Loan Agreement.

         11.  Binding  Agreement.  The  provisions  of this  Agreement  shall be
construed and interpreted,  and all rights and obligations of the parties hereto
determined,  in  accordance  with  the  internal  laws of the  State of New York
applicable to contracts made and to be performed in the State of New York.  This
Agreement,  together  with all  documents  referred to herein,  constitutes  the
entire  agreement  between the  parties  with  respect to the matters  addressed
herein  and  may  not  be  modified   except  by  a  writing   executed  by  the
Administrative  Agent and the Pledgor and delivered by the Administrative  Agent
to the Pledgor.

         12. Severability. If any paragraph or part thereof shall for any reason
be held or  adjudged  to be invalid,  illegal or  unenforceable  by any court of
competent  jurisdiction,  such paragraph or part thereof so adjudicated invalid,
illegal or unenforceable shall be deemed separate, distinct and independent, and
the remainder of this Agreement  shall remain in full force and effect and shall
not be affected by such holding or adjudication.

         13.  FCC  Compliance.  Notwithstanding  anything  herein  which  may be
construed to the contrary,  no action shall be taken by the Administrative Agent
which may require the consent or approval of the FCC,  and the proxy  granted in
Section  9(a)  hereof  shall  not  become   effective,   unless  and  until  all
requirements of the Communications  Act, requiring the consent to or approval of
such  action  by the FCC  have  been  satisfied.  The  Pledgor  covenants  that,
following and during the continuance of an Event of Default, upon request of the
Administrative  Agent, it will cause to be filed such applications and take such
other  action as may be  reasonably  requested  by the  Administrative  Agent to
obtain  consent  or  approval  of the  FCC to any  action  contemplated  by this
Agreement  and to give effect to the  security  interest  of the  Administrative
Agent,  including,  without  limitation,  the  execution of an  application  for
consent by the FCC to an assignment or transfer  involving a change in ownership
or control pursuant to the provisions of the Communications Act.


                                      - 6 -


<PAGE>



         14.   Counterparts.   This   Agreement  may  be  executed  in  multiple
counterparts,  each of which  shall be  deemed to be an  original,  but all such
separate counterparts shall together constitute but one and the same instrument.

         15.  Administrative  Agent.  Each reference herein to any right granted
to, benefit  conferred upon or power exercisable by the  "Administrative  Agent"
shall be a  reference  to the  Administrative  Agent for the  benefit of all the
Banks,  and each action taken or right  exercised  hereunder  shall be deemed to
have been so taken or exercised by the  Administrative  Agent for the benefit of
and on behalf of all the Banks.

                  [Remainder of Page Intentionally Left Blank]


                                      - 7 -


<PAGE>


         IN WITNESS WHEREOF,  the undersigned  parties hereto have executed this
Agreement by and through their duly authorized officers,  as of the day and year
first above written.


PLEDGOR:                                   ________________, a ____________


                                           By:
         [CORPORATE SEAL]                           Title:

                                           Attest:
                                                    Title:



ADMINISTRATIVE AGENT:                      TORONTO DOMINION (TEXAS),
                                           INC., as Administrative Agent


                                           By:
                                                    Title:



Schedule 1 - Shares Pledged Pursuant to Pledge Agreement
Schedule 2 - Outstanding Shares of Stock


SUBSIDIARY PLEDGE AGREEMENT
SIGNATURE PAGE 1

<PAGE>


                                    EXHIBIT I

                      FORM OF SUBSIDIARY SECURITY AGREEMENT


         THIS SUBSIDIARY  SECURITY  AGREEMENT (this "Agreement") dated as of the
___   day  of   _________,   1996,   by  and   between   __________________,   a
____________(the   "Subsidiary"),   and  Toronto  Dominion  (Texas),   Inc.,  as
administrative  agent (the  "Administrative  Agent") for itself and on behalf of
the Banks (as
defined in the Loan Agreement defined below).


                              W I T N E S S E T H:


         WHEREAS,  American Tower  Systems,  Inc., a Delaware  corporation  (the
"Borrower"),  the Banks and the  Administrative  Agent are all  parties  to that
certain Loan  Agreement  dated as of November 22, 1996 (as in effect on the date
hereof the "Loan Agreement"); and

         WHEREAS, pursuant to the terms of the Loan Agreement, the Subsidiary is
required to execute and deliver this Agreement;

         NOW,  THEREFORE,  in  consideration of the foregoing and for other good
and  valuable  consideration,  the receipt and  sufficiency  of which are hereby
acknowledged,  the parties hereto agree that capitalized terms used herein shall
have the  meanings  ascribed  to them in the Loan  Agreement  to the  extent not
otherwise defined or limited herein, and further agree as follows:

         1. Grant of Security Interest. Subject to the provisions of Sections 23
and 25 hereof,  and to the extent permitted by Applicable Law in the case of the
Licenses,  the  Subsidiary,  as a  direct  Subsidiary  of the  Borrower,  hereby
unconditionally  grants and assigns to the Administrative  Agent (for itself and
on behalf of the Banks) a continuing  security interest in and security title to
(hereinafter  referred to as the  "Security  Interest")  all of its property and
assets  and all  additions  thereto  and  replacements  thereof,  and all  other
property whether now owned or hereafter  created,  acquired or reacquired by the
Subsidiary, including:

Inventory

         All of the Subsidiary's inventory and supplies of whatsoever nature and
kind and wheresoever  situated,  including,  without limitation,  raw materials,
components,  work in process,  finished goods,  goods in transit and packing and
shipping materials,



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accretions and accessions thereto, trust receipts and similar documents covering
the same products (the "Inventory");

Accounts

         All right to payment for goods sold or leased or for services rendered,
expressly  including,  without limitation,  in connection with owning,  leasing,
managing and operating communications tower facilities, whether or not earned by
performance,  including,  without  limitation,  all agreements with and sums due
from  customers  and  other  Persons,  and  all  books  and  records  recording,
evidencing or relating to such rights or any part thereof (the "Accounts");

Equipment

         All machinery,  equipment and supplies  (installed and uninstalled) not
included in  Inventory  above,  including  motor  vehicles  and  accretions  and
accessions  thereto;  and  expressly  including,  without  limitation,   towers,
antennas  and  equipment  located  at  communications   tower  facilities;   any
distribution systems and all components thereof, including,  without limitation,
hardware,  cables,  fiber optic cables,  switches,  CODECs,  computer equipment,
amplifiers,  and associated devices;  and any other equipment used in connection
with the Subsidiary's business (the "Equipment");

Contracts and Leases

         All  assignable  (a)  construction  contracts,   subscriber  contracts,
customer service agreements,  management  agreements,  rights of way, easements,
pole attachment  agreements,  transmission  capacity agreements,  public utility
contracts and other  agreements to which the Subsidiary is a party,  whether now
existing or hereafter  arising,  including  without  limitation  those listed on
Exhibit A hereto (the  "Contracts");  (b) lease agreements for personal property
to which the Subsidiary is a party,  whether now existing or hereafter  arising,
including,  without limitation, those listed on Exhibit B hereto (the "Leases");
and (c) other  contracts and  contractual  rights,  remedies or  provisions  now
existing  or  hereafter   arising  in  favor  of  the  Subsidiary   (the  "Other
Contracts");

General Intangibles

         All general intangibles including personal property not included above,
such as, without limitation, all goodwill,  trademarks,  trademark applications,
trade names, trade secrets, industrial designs, other industrial or intellectual
property or rights therein,  whether under license or otherwise,  claims for tax
refunds, and tax refund amounts (the "Intangibles");


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Licenses

         To the extent  permitted by  Applicable  Law and subject to Sections 23
and  25  hereof,  all  franchises,   Licenses,   permits  and  operating  rights
authorizing  or relating  to the  Subsidiary's  rights to operate  and  maintain
communications   tower  facilities  or  similar  business   including,   without
limitation,  the  Licenses,  all as more  particularly  described  on  Exhibit C
attached hereto;

Furniture and Fixtures

         All furniture and fixtures in which the Subsidiary has an interest (the
"Furniture and Fixtures");

Miscellaneous Items

         All goods, chattel paper, documents,  instruments,  supplies, choses in
action,  claims,  money,  deposits,  certificates  of  deposit,  stock  or share
certificates,  and  licenses  and other  rights  in  intellectual  property  not
included above (the "Miscellaneous Items"); and

Proceeds

         All  proceeds  of any of the above,  and all  proceeds  of any loss of,
damage to or destruction of the above,  whether insured or not insured,  and all
other  proceeds  of any sale,  lease or other  disposition  of any  property  or
interest therein referred to above including,  without limitation,  the proceeds
of the sale of any  License,  together  with all  proceeds  of any  policies  of
insurance  covering  any or all of the  above,  the  proceeds  of any  award  in
condemnation with respect to any of the property of the Subsidiary,  any rebates
or refunds,  whether for taxes or  otherwise,  together with all proceeds of any
such proceeds (the "Proceeds").

         The Inventory, Accounts, Equipment, Contracts, Other Contracts, Leases,
Intangibles,   Licenses,  Furniture  and  Fixtures,   Miscellaneous  Items,  and
Proceeds,  as described above, are hereinafter  collectively  referred to as the
"Collateral."

         This Agreement and the Security Interest secure payment and performance
of all obligations of the Subsidiary to the Banks and the Administrative  Agent,
or any of them, under that certain Subsidiary Guaranty of even date given by the
Subsidiary for the benefit of the Banks and the  Administrative  Agent,  and any
extensions,  renewals or amendments thereto, however created,  acquired, arising
or  evidenced,  whether  direct or  indirect,  absolute  or  contingent,  now or
hereafter existing,  or due or to become due, (all of the foregoing  obligations
being hereinafter collectively referred to as the "Obligations").



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         2.  Further   Assurances.   The   Subsidiary   hereby   authorizes  the
Administrative  Agent to file such financing statements and such other documents
as the  Administrative  Agent may  reasonably  require to protect or perfect the
interest of the Banks and the  Administrative  Agent in the Collateral,  and the
Subsidiary  further  irrevocably   appoints  the  Administrative  Agent  as  its
attorney-in-fact,  with  a  power  of  attorney  to  execute  on  behalf  of the
Subsidiary such UCC financing  statement forms as the  Administrative  Agent may
from time to time  reasonably  deem necessary or desirable to protect or perfect
such  interest in the  Collateral.  Such power of  attorney  is coupled  with an
interest and shall be  irrevocable.  In addition,  the Subsidiary  agrees to do,
execute and deliver or cause to be done, executed and delivered all such further
acts,  documents and things as the  Administrative  Agent may reasonably require
for the  purpose of  perfecting  or  protecting  the rights of the Banks and the
Administrative Agent hereunder or otherwise giving effect to this Agreement, all
promptly upon request therefor.

         3.  Representations  and  Warranties.  The  Subsidiary  represents  and
warrants to the Banks and the Administrative Agent that:

                  (a) the execution of this Agreement and the fulfillment of the
         terms  hereof  will  not  result  in a  breach  of any of the  terms or
         provisions of, or constitute a default under, the Subsidiary's Articles
         of Incorporation or By-Laws as currently in effect,  or any order, rule
         or  regulation  applicable  to the  Subsidiary  of any  court or of any
         Federal  or state  regulatory  body or  administrative  agency or other
         governmental body having jurisdiction over the Subsidiary, or result in
         the termination or  cancellation or breach of any indenture,  mortgage,
         deed of  trust,  deed to  secure  debt,  lease  or other  agreement  or
         instrument  to which the  Subsidiary is a party or by which it is bound
         or affected;

                  (b) the Subsidiary has taken all necessary corporate action to
         authorize  the  execution  and  delivery  of this  Agreement,  and this
         Agreement,  when executed and delivered,  will be the valid and binding
         obligation of the Subsidiary  enforceable in accordance with its terms,
         subject only to the following qualifications:

                           (i)      certain equitable remedies are discretionary
                  and, in particular, may not be available where damages
                  are considered an adequate remedy at law,

                           (ii)   enforcement  may  be  limited  by  bankruptcy,
                  insolvency,  liquidation,  reorganization,  reconstruction and
                  other similar laws affecting  enforcement of creditors' rights
                  generally (insofar as any such law


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                  relates to the bankruptcy, insolvency or similar event
                  of the Subsidiary), and

                     (iii)          enforcement as to the Licenses is limited by
                  FCC rules and regulations restricting the transfer of
                  such Licenses.

                  (c) Exhibit A attached hereto and incorporated  herein by this
         reference  sets forth a complete and accurate  list of the Contracts in
         effect on the date hereof which provide for aggregate payments over the
         life of each such Contract in excess of $100,000 or which are otherwise
         material to the  Subsidiary,  and the  Subsidiary  will furnish  copies
         thereof to the Banks and the  Administrative  Agent upon the request of
         the Administrative Agent;

                  (d) Exhibit B attached hereto and incorporated  herein by this
         reference  sets  forth a  complete  and  accurate  list  of all  Leases
         providing for  aggregate  payments over the life of any single Lease in
         excess of $250,000, to which the Subsidiary is a party in effect on the
         date hereof,  and the  Subsidiary  will furnish  copies  thereof to the
         Banks  and  the   Administrative   Agent   upon  the   request  of  the
         Administrative Agent; and

                  (e) Exhibit C attached hereto and incorporated  herein by this
         reference  sets forth a complete and  accurate  list of the Licenses in
         effect on the date hereof.

         4. Representations and Warranties Concerning Collateral. The Subsidiary
further represents and warrants that (a) the Security Interest in the Collateral
granted  hereunder shall constitute at all times a valid first priority security
interest (subject only to Permitted Liens),  vested in the Administrative Agent,
in and upon the Collateral,  free of any Liens except for Permitted  Liens,  (b)
the location of the  Inventory  and the  Equipment is as set forth on Schedule 1
hereto,  and (c) none of the Accounts are  represented  by  promissory  notes or
other instruments.  The Subsidiary shall take or cause to be taken such acts and
actions  as shall be  necessary  or  appropriate  to  assure  that the  Security
Interest  in the  Collateral  shall  not  become  subordinate  or  junior to the
security interests, liens or claims of any other Person, and that the Collateral
shall not  otherwise  be or become  subject to any Lien,  except  for  Permitted
Liens.

         5. Location of Books and Records. The Subsidiary further represents and
warrants  that  it now  keeps  all  of  its  records  concerning  its  Accounts,
Contracts,  Leases,  Other  Contracts,  and  Intangibles at its chief  executive
office,  except as listed on  Exhibit D hereto.  The  Subsidiary  covenants  and
agrees that it shall not keep any of such records at any other  address,  unless
written notice thereof is given to the Administrative Agent at least thirty (30)
days prior to the creation of any new address


                                       -5-


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for the keeping of such records.  The  Subsidiary  further  agrees that it shall
promptly advise the  Administrative  Agent, in writing making  reference to this
Section  4 of this  Agreement,  of the  opening  of any  material  new  place of
business,  the closing of any existing material place of business, or any change
in the  location  of the  place  where it keeps the  Collateral  or of its chief
executive officer.

         6.  Collateral  Not  Fixtures.  The parties  intend that, to the extent
permitted by  Applicable  Law, the  Collateral  shall remain  personal  property
irrespective of the manner of its attachment or affixation to realty.

         7. Covenants  Regarding  Collateral.  Any and all injury to, or loss or
destruction of, the Collateral shall be at the Subsidiary's  risk, and shall not
release the Subsidiary from its obligations hereunder. The Subsidiary agrees not
to sell, transfer,  assign, dispose of, mortgage,  grant a security interest in,
or encumber any of the Collateral  except as permitted under the Loan Agreement.
The  Subsidiary  agrees to maintain in force such  insurance with respect to the
Collateral as is required under the Loan Agreement. The Subsidiary agrees to pay
all required  taxes,  liens,  and assessments  upon the  Collateral,  its use or
operation,  as required under the Loan Agreement.  The Subsidiary further agrees
that the  Administrative  Agent  may,  but  shall in no event be  obligated  to,
following written notice to the Subsidiary, insure any of the Collateral in such
form and amount as the  Administrative  Agent may deem necessary or desirable if
the Subsidiary fails to obtain insurance as required by the Loan Agreement,  and
that the  Administrative  Agent may pay or discharge any taxes if the Subsidiary
fails to pay such taxes as required by the Loan  Agreement  or Liens  (which are
not Permitted Liens) on any of the Collateral,  and the Subsidiary agrees to pay
any such sum so  expended  by the  Administrative  Agent,  with  interest at the
Default Rate,  and such amounts shall be deemed to be a part of the  Obligations
secured by the Collateral under the terms of this Agreement.

         8.  Covenants  Regarding  Contracts,  Other  Contracts and Leases.  The
Subsidiary  shall (a)  fulfill,  perform  and  observe  each and every  material
condition and covenant contained in any of the Contracts, the Other Contracts or
the Leases,  other than those being  contested in good faith or unless the other
party thereto is in default,  (b) give prompt notice to the Administrative Agent
of any claim of material  default  under any Contract,  Other  Contract or Lease
given to the  Subsidiary  or by the  Subsidiary  other than  those  which in the
Subsidiary's  reasonable business judgment are no longer in the best interest of
the  Subsidiary  to  enforce  and which  have been  previously  approved  by the
Administrative  Agent,  (c) at the sole  cost  and  expense  of the  Subsidiary,
enforce the performance  and observance of each and every material  covenant and
condition of the Contracts, the Other Contracts and the Leases to which it is a


                                       -6-


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party other than those which in the Subsidiary's  reasonable  business  judgment
are no longer in the best  interest of the  Subsidiary to enforce and which have
been  previously  approved by the  Administrative  Agent,  and (d) appear in and
defend any action  growing out of or in any manner  connected with any Contract,
Other Contract or Lease to which it is a party. The rights and interests granted
to the Administrative Agent hereunder include all of the Subsidiary's rights and
title (i) to modify the Contracts,  the Other Contracts and the Leases,  (ii) to
terminate the Contracts,  the Other Contracts and the Leases, and (iii) to waive
or release the  performance  or observance of any obligation or condition of the
Contracts,  the Other  Contracts  and the Leases;  provided,  however,  that the
Subsidiary shall have the right to exercise these rights in a fashion consistent
with this  Agreement  prior to any Event of Default and that these  rights shall
not be exercised by the Administrative  Agent prior to the occurrence and during
the continuation of an Event of Default.

         9.  Remedies.  Upon the occurrence  and during the  continuation  of an
Event of Default,  the Banks and the Administrative Agent shall have such rights
and remedies as are set forth in the Loan  Agreement,  the other Loan  Documents
and herein,  all the rights,  powers and privileges of a secured party under the
Uniform  Commercial  Code of the  State  of New York  and any  other  applicable
jurisdiction,  and all other rights and remedies  available to the Banks and the
Administrative  Agent,  or any of  them,  at law or in  equity.  The  Subsidiary
covenants  and agrees  that any  notification  of  intended  disposition  of any
Collateral,  if such notice is required by law,  shall be deemed  reasonably and
properly given if given in the manner provided for in Section 20 hereof at least
ten  (10)  days  prior  to  such  disposition.  Under  such  circumstances,  the
Administrative  Agent shall have the right to the  appointment of a receiver for
the properties and assets of the Subsidiary,  and the Subsidiary hereby consents
to such rights and to such  appointment  and hereby  waives any objection it may
have thereto and hereby waives the right to have a bond or other security posted
by the  Administrative  Agent or any other Person in connection  therewith.  The
Subsidiary  agrees,  after the  occurrence  of an Event of Default,  to take any
actions that the Administrative  Agent may reasonably request in order to enable
the  Administrative  Agent to  obtain  and enjoy the full  rights  and  benefits
granted to the  Administrative  Agent  under this  Agreement  and the other Loan
Documents.  Without  limiting the  generality of the  foregoing,  the Subsidiary
shall, at the Subsidiary's cost and expense,  use its reasonable best efforts to
assist in obtaining  all approvals of the FCC which are then required by law for
or in connection  with any action or transaction  contemplated by this Agreement
or  Article 9 of the  Uniform  Commercial  Code as in  effect in any  applicable
jurisdiction, and, at the Administrative Agent's request, prepare, sign and file
with the FCC the  assignor's  or  transferor's  portion  of any  application  or
applications  for  consent to the  assignment  of the  Licenses  or  transfer of
control


                                       -7-


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thereof  necessary or appropriate under the FCC's rules for approval of any sale
or transfer of the  Administrative  Agent's  remedies under this Agreement.  The
Administrative  Agent shall have the right,  in connection  with the issuance of
any order for relief in a  bankruptcy  proceeding,  to petition  the  bankruptcy
court for the transfer of control or  assignment  of the Licenses to a receiver,
trustee,  transferee,  or similar official or to any purchaser of the Collateral
pursuant  to any  public or  private  sale,  foreclosure  or other  exercise  of
remedies available to the  Administrative  Agent, all as permitted by Applicable
Law.  All  amounts  realized  or  collected  through  the  exercise  of remedies
hereunder shall be applied to the Obligations as provided in the Loan Agreement.

         10. Notification of Account Debtors. Upon the occurrence and during the
continuation  of an Event of Default,  the  Administrative  Agent may notify the
account  debtors  that all  payments  with  respect to  Accounts  are to be paid
directly  to the  Administrative  Agent and any  amount  thereafter  paid to the
Subsidiary  shall be received in trust by the  Subsidiary for the benefit of the
Administrative  Agent and segregated from other funds of the Subsidiary and paid
over to the  Administrative  Agent  in the  form  received  (together  with  any
necessary endorsements).

         11. Remedies of  Administrative  Agent. Upon the occurrence of an Event
of Default and during the continuation  thereof, the Administrative Agent or its
designee may proceed to perform any and all of the obligations of the Subsidiary
contained in any of the  Contracts,  Other  Contracts or Leases and exercise any
and all rights of the  Subsidiary  therein  contained as fully as the Subsidiary
itself  could.  The  Subsidiary  hereby  appoints the  Administrative  Agent its
attorney-in-fact,  with power of substitution, to take such action, execute such
documents,   and  perform  such  work  as  the  Administrative  Agent  may  deem
appropriate  in  exercise of the rights and  remedies  granted the Banks and the
Administrative  Agent,  or any of them,  herein  or in any other  Loan  Document
following  written  notice to the  Subsidiary.  The powers herein  granted shall
include,  without  limitation,  powers to: (a) sue on the  Contracts,  the Other
Contracts or the Leases;  (b) seek all  governmental  approvals  (other than FCC
approvals)  required for the  operation of the business of the  Subsidiary;  (c)
modify or terminate the Contracts,  the Other Contracts and the Leases;  and (d)
waive or release the  performance or observance of any  obligation  under any of
the Contracts,  Other Contracts or Leases.  The power of attorney granted herein
is coupled with an interest and shall be irrevocable.

         12. Additional Remedies. Upon the occurrence of an Event of Default and
during  the  continuation  thereof,  should  the  Subsidiary  fail to perform or
observe  any  covenant  or comply  with any  condition  contained  in any of the
Contracts,  the Other Contracts or the Leases,  then following written notice to
the


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Subsidiary,  the  Administrative  Agent may, but without obligation to do so and
without  releasing the  Subsidiary  from its  obligation to do so,  perform such
covenant or  condition  and, to the extent that the  Administrative  Agent shall
incur  any  reasonable  costs  or pay  any  expenses  in  connection  therewith,
including any reasonable costs or expenses of litigation  associated  therewith,
such costs,  expenses or payments shall be included in the  Obligations  secured
hereby and shall bear interest from the payment of such costs or expenses by the
Administrative  Agent at the Default Rate. Neither the Administrative  Agent nor
any Bank  shall be  obliged  to  perform  or  discharge  any  obligation  of the
Subsidiary under any of the Contracts,  the Other Contracts or the Leases,  and,
except as may result from the bad faith,  gross negligence or willful misconduct
of the Person seeking  indemnification,  the Subsidiary  agrees to indemnify and
hold  the  Administrative  Agent  and each  Bank  harmless  against  any and all
liability,  loss or damage  which  any such  Person  may incur  under any of the
Contracts,  the  Other  Contracts  or the  Leases  or under or by reason of this
Agreement,  and any and all claims and demands  whatsoever which may be asserted
against the  Subsidiary by reason of an act of the  Administrative  Agent or any
Bank under any of the terms of this Agreement or under the Contracts,  the Other
Contracts or the Leases.

         13.  Administrative  Agent May Collect Accounts.  The Subsidiary hereby
further appoints the Administrative Agent as its attorney-in-fact, with power of
substitution, with authority to collect all Accounts, to endorse the name of the
Subsidiary on any note, acceptance,  check, draft, money order or other evidence
of debt or of payment which  constitutes a portion of the  Collateral  and which
may come into the possession of the Banks and the  Administrative  Agent, or any
of them,  and  generally  to do such  other  things  and acts in the name of the
Subsidiary  with respect to the  Collateral as are necessary or  appropriate  to
protect or  enforce  the rights  hereunder  of the Banks and the  Administrative
Agent. The Subsidiary  further authorizes the  Administrative  Agent,  effective
upon the occurrence of an Event of Default and during the continuation  thereof,
to  compromise  and settle or to sell,  assign or transfer  or to ask,  collect,
receive or issue any and all claims possessed by the Subsidiary which constitute
a portion of the Collateral, all in the name of the Subsidiary.  After deducting
all  reasonable  expenses  and charges  (including  the  Administrative  Agent's
attorneys' fees) of retaking,  keeping, storing and selling the Collateral,  the
Administrative Agent may apply the proceeds in payment of any of the Obligations
in the  order of  application  set  forth in the Loan  Agreement.  The  power of
attorney  granted  herein is coupled with an interest and shall be  irrevocable.
The Subsidiary agrees that a failure to so notify the Administrative Agent shall
be a  waiver  and  bar to any  subsequent  claim  for  any  such  property.  The
Subsidiary agrees that if steps are taken by the Administrative Agent to enforce
its rights hereunder,  or to realize upon any of the Collateral,  the Subsidiary
shall pay to the Administrative


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Agent the  amount of the  Administrative  Agent's  reasonable  costs,  including
attorneys'  fees, and the  Subsidiary's  obligation to pay such amounts shall be
deemed to be a part of the Obligations  secured  hereunder.  Upon the occurrence
and  during  the  continuation  of an Event of  Default,  the  Subsidiary  shall
segregate all proceeds of any Collateral from other assets of the Subsidiary.

         14.  Indemnification.  The Subsidiary shall indemnify and hold harmless
the  Administrative  Agent, each Bank, and any other Person acting hereunder for
all losses,  costs,  damages,  fees and expenses whatsoever  associated with the
exercise  of the  powers  of  attorney  granted  herein  and shall  release  the
Administrative  Agent, each Bank, and any other Person acting hereunder from all
liability  whatsoever  for the exercise of the foregoing  powers of attorney and
all actions taken pursuant thereto,  except, in either event, in the case of bad
faith,   gross   negligence  or  willful   misconduct  by  the  Person   seeking
indemnification.

         15. Remedies  Cumulative.  The Subsidiary agrees that the rights of the
Banks and the  Administrative  Agent, or any of them, under this Agreement,  the
Loan Agreement,  any other Loan Document, or any other contract or agreement now
or hereafter in existence among the Banks and the  Administrative  Agent and the
Subsidiary  and  the  other  obligors  thereunder,  or any  of  them,  shall  be
cumulative,  and that the  Administrative  Agent  and each Bank may from time to
time  exercise  such rights and such remedies as such Person or Persons may have
thereunder and under the laws of the United States or any state,  as applicable,
in the manner  and at the time that such  Person or Persons in its or their sole
discretion  desire,  subject  to the terms of such  agreements.  The  Subsidiary
further expressly agrees that the Banks and the Administrative Agent shall in no
event be under any obligation to resort to any  Collateral  secured hereby prior
to exercising any other rights that the Banks and the  Administrative  Agent, or
any of them,  may have against the  Subsidiary  or its  property,  nor shall the
Banks and the Administrative  Agent be obliged to resort to any other collateral
or  security  for the  Obligations,  other  than  the  Collateral,  prior to any
exercise of the  Administrative  Agent's  rights  against the Subsidiary and its
property hereunder.

         16.   Obligations   Commercial  in  Nature.   The   Subsidiary   hereby
acknowledges  that the Obligations  arose out of a commercial  transaction,  and
agrees  that  if an  Event  of  Default  shall  occur  and  be  continuing,  the
Administrative  Agent shall, to the extent permitted by Applicable Law, have the
right to immediate  possession without notice or a hearing, and hereby knowingly
and intelligently waives, to the extent permitted by Applicable Law, any and all
rights  it may have to any  notice  and  posting  of a bond by the Banks and the
Administrative  Agent,  or any of them,  prior to seizure by the  Administrative
Agent or any of its  transferees,  assigns  or  successors  in  interest  of the
Collateral or any portion thereof.


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<PAGE>




         17.  Amendments  and  Waivers.  No  amendment,   modification,  waiver,
transfer or renewal,  extension,  assignment or termination of this Agreement or
of the Loan  Agreement or of any other Loan  Document,  or of any  instrument or
document  executed and  delivered by the  Subsidiary or any other obligor to the
Banks and the Administrative Agent, or any of them, nor additional advances made
by the Banks and the Administrative Agent, or any of them, to the Borrower,  nor
the taking of further  security,  nor the retaking or  re-delivery or release of
the Collateral to the Subsidiary by the Banks and the  Administrative  Agent, or
any of them, nor any lack of validity or  enforceability of any Loan Document or
any term thereof,  nor any other act of the Banks and the Administrative  Agent,
or any of them,  shall  release the  Subsidiary  from any  Obligation,  except a
release  or  discharge  executed  in  writing  by the  Administrative  Agent  in
accordance  with the Loan Agreement with respect to such Obligation or upon full
payment and  satisfaction  of all Obligations and termination of the Commitment.
Neither the Administrative Agent nor any Bank shall by any act, delay,  omission
or  otherwise,  be deemed to have waived any of its or their  rights or remedies
hereunder,  unless such  waiver is in writing  and signed by the  Administrative
Agent in accordance  with the Loan Agreement and then only to the extent therein
set forth. A waiver by the Banks and the  Administrative  Agent, or any of them,
of any right or remedy on any  occasion  shall not be  construed as a bar to the
exercise of any such right or remedy which any such Person would  otherwise have
had on any other occasion.

         18. Assignment. The Subsidiary agrees that this Agreement or the rights
hereunder may in the discretion of the Banks and the  Administrative  Agent,  or
any of them, as applicable,  be assigned in whole or in part in connection  with
any assignment of the Loan Agreement or the Obligations arising  thereunder,  as
permitted thereunder. In the event this Agreement or the rights hereunder are so
assigned by any of the Banks and the Administrative  Agent, the terms "Banks" or
"Administrative  Agent" wherever used herein shall be deemed, as applicable,  to
refer to and include any such assignee.

         19. Successors and Assigns.  This Agreement shall apply to and bind the
respective  successors and permitted  assigns of the Subsidiary and inure to the
benefit of the successors and permitted assigns of the Subsidiary, the Banks and
the Administrative Agent.

         20. Notices. All notices and other communications required or permitted
hereunder  shall be in  writing  and shall be given in a fashion  prescribed  in
Section  11.1  of  the  Loan  Agreement  with  respect  to  the  Banks  and  the
Administrative  Agent, and in the fashion prescribed in Section 11.1 of the Loan
Agreement  with  respect to the  Subsidiary  to the address of the  Borrower set
forth in or otherwise provided pursuant to the Loan Agreement.



                                      -11-


<PAGE>



         21.  Governing Law. The provisions of this Agreement shall be construed
and  interpreted,   and  all  rights  and  obligations  of  the  parties  hereto
determined,  in  accordance  with  the  internal  laws of the  State of New York
applicable to contracts made and to be performed in the State of New York.  This
Agreement,  together  with all  documents  referred to herein,  constitutes  the
entire agreement among the Subsidiary and the Banks and the Administrative Agent
with respect to the matters addressed herein and may not be modified except by a
writing executed by the Administrative Agent and delivered to the Subsidiaries.

         22.  Severability.  If any paragraph or part thereof of this  Agreement
shall for any reason be held or adjudged to be invalid, illegal or unenforceable
by any court of  competent  jurisdiction,  such  paragraph  or part  thereof  so
adjudicated invalid, illegal or unenforceable shall be deemed separate, distinct
and independent,  and the remainder of this Agreement shall remain in full force
and effect and shall not be affected by such holding or adjudication.

         23. FCC Consent. Notwithstanding anything herein which may be construed
to the  contrary,  no action  shall be taken by the  Administrative  Agent  with
respect to the Licenses  issued by the FCC unless and until all  requirements of
Applicable Law, including,  without limitation,  any required approval under the
Communications Act, including without limitation the provision for ten (10) days
notice to the FCC required by 47 C.F.R. ss. 22.917(e),  requiring the consent to
or approval of such action by the FCC or any  governmental  or other  authority,
have  been  satisfied.  The  Subsidiary  covenants  that  upon  request  of  the
Administrative  Agent it will cause to be filed such  applications and take such
other  action as may be  reasonably  requested  by the  Administrative  Agent to
obtain the consent or approval of the FCC or any governmental or other authority
which has granted any License to the  Subsidiary to any action  contemplated  by
this Agreement and to give effect to the Security Interest of the Administrative
Agent,  including,  without  limitation,  the  execution of an  application  for
consent by the FCC to an assignment or transfer  involving a change in ownership
or control pursuant to the provisions of the Communications Act.

         24.  Counterparts.  This  Agreement  may be  executed  in any number of
counterparts,  each of which  shall be  deemed to be an  original,  but all such
separate counterparts shall together constitute but one and the same instrument.

         25.  Changes in Applicable  Law. The parties  acknowledge  their intent
that,  upon the  occurrence  of an Event of Default  and during the  continuance
thereof, the Administrative Agent shall receive, to the fullest extent permitted
by Applicable Law and governmental policy (including,  without  limitation,  the
rules,  regulations and policies of the FCC), all rights  necessary or desirable
to obtain, use or sell the Collateral and to exercise


                                      -12-


<PAGE>



all remedies  available to it under this Agreement,  the Uniform Commercial Code
as in  effect in any  applicable  jurisdiction,  or other  Applicable  Law.  The
parties  further  acknowledge  and agree that, in the event of changes in law or
governmental  policy occurring  subsequent to the date hereof that affect in any
manner the  Administrative  Agent's  rights of access to, or use or sale of, the
Collateral,  or the procedures  necessary to enable the Administrative  Agent to
obtain  such rights of access,  use or sale,  the  Administrative  Agent and the
Subsidiary shall amend this Agreement in such manner as the Administrative Agent
shall  reasonably  request in order to  provide  the  Administrative  Agent such
rights to the  greatest  extent  possible  consistent  with  Applicable  Law and
governmental policy.

         26.  Administrative  Agent.  Each reference herein to any right granted
to, benefit  conferred upon or power exercisable by the  "Administrative  Agent"
shall be a  reference  to the  Administrative  Agent for the  benefit of all the
Banks,  and each action taken or right  exercised  hereunder  shall be deemed to
have been so taken or exercised by the  Administrative  Agent for the benefit of
and on behalf of all the Banks.


                  [Remainder of Page Intentionally Left Blank]


                                      -13-


<PAGE>


         IN WITNESS  WHEREOF,  the undersigned have hereunto set their hands, by
and through their duly authorized representatives,  as of the day and year first
written above.


SUBSIDIARY:                            __________________, INC., a ____________


                                       By:

                                                 Its:

[CORPORATE SEAL]
                                       Attest:

                                                 Its:




ADMINISTRATIVE AGENT:                  TORONTO DOMINION (TEXAS), INC., as
                                       Administrative Agent


                                       By:

                                                 Its:





SUBSIDIARY SECURITY AGREEMENT
Signature Page 1


<PAGE>


                                    EXHIBIT J

                         FORM OF USE OF PROCEEDS LETTER

                             As of ________ __, ____


Toronto Dominion (Texas), Inc.,
  as Administrative Agent
909 Fannin Street
Suite 1700
Houston, Texas  77010

                  Re:      $90,000,000 Loans to American Tower Systems, Inc.

Ladies and Gentlemen:

         We refer to the Loan  Agreement  dated as of  November  22, 1996 (as in
effect on the date hereof, the "Loan Agreement"),  among American Tower Systems,
Inc., a Delaware corporation (the "Borrower"), the Banks (as defined in the Loan
Agreement) and Toronto Dominion (Texas),  Inc., as administrative  agent for the
Banks (in such  capacity,  the  "Administrative  Agent"),  pursuant to which and
subject to the terms and  conditions  whereof the Banks  agreed to make loans to
the  Borrower.  Unless  otherwise  defined  herein,  terms  defined  in the Loan
Agreement are used herein as therein defined.

         The Borrower hereby certifies to the Administrative Agent and the Banks
that the proceeds of the Advance made under the Commitment on ___________  ____,
____ shall be used as follows:

         ______________________________________________________
         ______________________________________________________
         ______________________________________________________

         Attached  hereto  is  a  sources  and  uses  statement  describing  the
transactions contemplated to occur on __________ __, ____.


                                       AMERICAN TOWER SYSTEMS, INC., a Delaware
                                       corporation



                                       By:

                                               Its:


<PAGE>


                                    EXHIBIT K

                       FORM OF BORROWER'S LOAN CERTIFICATE

                          AMERICAN TOWER SYSTEMS, INC.


         The    undersigned,    _________________,    as   the   duly    elected
___________________ of American Tower Systems, Inc., a Delaware corporation (the
"Corporation"), hereby certifies, that:

         1.  The  following  persons  are,  on and as of the date  hereof,  duly
elected  officers of the  Corporation  holding the office(s) set opposite  their
respective names, and the signatures set opposite their respective names are the
true signatures of said officers:

       Name                      Office                    Signature

-----------------          ------------------      --------------------------

-----------------          ------------------      --------------------------

-----------------          ------------------      --------------------------


         2.  Exhibit  A  attached  hereto  is a true  and  complete  copy of the
resolutions duly adopted by the Board of Directors of the Corporation;  and such
resolutions  have not been  amended,  modified or  rescinded  and remain in full
force and effect as of the date hereof.

         3.  Exhibit  B  attached  hereto  is a true  and  complete  copy of the
Certificate of  Incorporation  of the Corporation and all amendments  thereto in
effect on the date hereof.

         4. Exhibit C attached hereto is a true and complete copy of the By-Laws
of the Corporation together with all amendments thereto as of the date hereof.

         5. Exhibit D attached  hereto are true,  complete and correct copies of
certificates  of good  standing for the Borrower from the Secretary of State for
the State of Delaware and for each other  jurisdiction  in which the Borrower is
required to qualify to do business in order to transact  the  business  which it
transacts in such jurisdiction in accordance with Applicable Law, subject to the
provisions  of the Loan  Agreement.  The  Borrower  has,  from the dates of such
certificates, remained in good standing under the laws of such states.



<PAGE>


         6.  Exhibit E attached  hereto is a true,  complete and correct copy of
any  shareholders'  agreements or voting trust agreements in effect with respect
to the stock of the Borrower.

         IN   WITNESS   WHEREOF,   the   undersigned    _________________,    as
___________________   of  American  Tower  Systems,   Inc.,  has  executed  this
Certificate as of the ____ day of November, 1996.


                                     AMERICAN TOWER SYSTEMS, INC., a Delaware
                                     corporation



                                     By:
                                              Name:
                                              Title:



EXHIBITS

Exhibit A - Authorizing Resolutions
Exhibit B - Certificate of Incorporation
Exhibit C - By-laws
Exhibit D - Good-Standing Certificates
Exhibit E - Shareholders' or Voting Trust Agreements


                                       -2-

<PAGE>


                                    EXHIBIT L

                       FORM OF SUBSIDIARY LOAN CERTIFICATE

                              [NAME OF SUBSIDIARY]


         The  undersigned,   _________________________,   as  the  duly  elected
_____________________  of  ________________,   a  ___________  corporation  (the
"Corporation"), hereby certifies, that:

         1.  The  following  persons  are,  on and as of the date  hereof,  duly
elected  officers of the  Corporation  holding the office(s) set opposite  their
respective names, and the signatures set opposite their respective names are the
true signatures of said officers:

     Name                          Office                         Signature

-----------------           -------------------           ----------------------

-----------------           -------------------           ----------------------

-----------------           -------------------           ----------------------


         2.  Exhibit  A  attached  hereto  is a true  and  complete  copy of the
resolutions duly adopted by the Board of Directors of the Corporation;  and such
resolutions  have not been  amended,  modified or  rescinded  and remain in full
force and effect as of the date hereof.

         3.  Exhibit  B  attached  hereto  is a true  and  complete  copy of the
Certificate of  Incorporation  of the Corporation and all amendments  thereto in
effect on the date hereof.

         4. Exhibit C attached hereto is a true and complete copy of the By-Laws
of the Corporation together with all amendments thereto as of the date hereof.

         IN  WITNESS  WHEREOF,   the  undersigned   ______________________,   as
______________________ of  _____________________,  has executed this Certificate
as of the _____ day of November, 1996.

                                           [NAME OF SUBSIDIARY], a __________
                                           corporation



                                           By:
                                                    Name:
                                                    Title:


EXHIBITS

Exhibit A - Authorizing Resolutions
Exhibit B - Certificate of Incorporation
Exhibit C - By-laws


<PAGE>


                                    EXHIBIT M

                         FORM OF PERFORMANCE CERTIFICATE

         The undersigned  hereby certifies that he or she is the Chief Financial
Officer  of  American  Tower  Systems,   Inc.,  a  Delaware   corporation   (the
"Borrower"). In connection with that certain Loan Agreement dated as of November
22, 1996 (as in effect on the date hereof,  the "Loan  Agreement")  by and among
the Borrower,  the Banks (as defined in the Loan Agreement) and Toronto Dominion
(Texas),  Inc., as  administrative  agent for the Banks (in such  capacity,  the
"Administrative  Agent"),  the  undersigned  does hereby  certify,  as the Chief
Financial Officer of and on behalf of the Borrower, that:

         1.       Calculations  demonstrating  the interest rate adjustment,  as
                  provided for in Section 2.3(f) of the Loan Agreement,  for the
                  [quarter/year]  ended  ______________,  199_, are set forth on
                  Schedule 1 attached hereto;

         2.       Calculations  demonstrating compliance with Sections 7.7, 7.8,
                  7.9,  7.10  and 7.11 of the Loan  Agreement  are set  forth on
                  Schedule 2 attached hereto; and

         4.       To the knowledge of the undersigned after due inquiry of other
                  officers of the  Borrower,  no Default or Event of Default has
                  occurred during or as at the end of such [quarter/year].

         Capitalized  terms used  herein and not  otherwise  defined are used as
defined in the Loan Agreement.

         IN WITNESS WHEREOF, I have executed this Performance  Certificate as of
__________________, ____.


                                                AMERICAN TOWER SYSTEMS, INC., a
                                                Delaware corporation



                                                By:
                                                         Name:
                                                         Chief Financial Officer


<PAGE>


                                    EXHIBIT N

                   FORM OF ASSIGNMENT AND ASSUMPTION AGREEMENT


         This Assignment and Assumption Agreement is made and entered into as of
____________ ____, ____, by and between  _______________________________________
(the  "Assignor"),   and   ______________________________________________   (the
"Assignee").

                                    Recitals

         A.  American  Tower  Systems,   Inc.,  a  Delaware   corporation   (the
"Borrower"),  the Assignor and certain other  financial  institutions  (together
with any other person which becomes a 'Bank' under the Loan  Agreement,  as such
term is hereinafter defined, the "Banks"),  and Toronto Dominion (Texas),  Inc.,
as  administrative  agent for the Banks (in such capacity,  the  "Administrative
Agent"),  are parties to a certain Loan Agreement  dated as of November 22, 1996
(as the same has been amended,  modified or supplemented  from time to time, the
"Loan  Agreement").  Pursuant  to the Loan  Agreement,  the Banks have agreed to
extend  credit to the Borrower  under the  Commitment,  of which the  Assignor's
portion of the Commitment is the amount specified in Item 1 of Schedule 1 hereto
(the "Assignor's Commitment"). The principal amount of outstanding Loans made by
the Assignor to the Borrower pursuant to the Assignor's  Commitment is specified
in Item 2 of Schedule 1 hereto (the "Assignor's  Loans").  All capitalized terms
not otherwise defined herein are used herein as defined in the Loan Agreement.

         B. The  Assignor  wishes to sell and  assign to the  Assignee,  and the
Assignee wishes to purchase and assume from the Assignor, (i) the portion of the
Assignor's  Commitment  specified  in  Item 3 of  Schedule  1  hereto  which  is
equivalent to the  percentage of  Assignor's  Commitment  specified in Item 4 of
Schedule 1 ("Assigned Commitment"), and (ii) the portion of the Assignor's Loans
under the  Commitment  specified  in Item 5 of Schedule 1 hereto (the  "Assigned
Loans").

         The parties agree as follows:

         1.  Assignment.  Subject to the terms and  conditions set forth herein,
the  Assignor  hereby  sells  and  assigns  to the  Assignee,  and the  Assignee
purchases and assumes from the Assignor,  without  recourse to the Assignor,  on
the date set forth  above (the  "Assignment  Date") (a) all  right,  title,  and
interest of the Assignor to the Assigned  Loans and (b) all  obligations  of the
Assignor under the Loan Agreement  with respect to the Assigned  Commitment.  As
full consideration for the sale of the


<PAGE>



Assigned  Loans  and the  Assigned  Commitment,  the  Assignee  shall pay to the
Assignor on the Assignment Date such amount as shall have been agreed to between
the Assignor and the Assignee (the "Purchase Price").

         2. Consents and Undertaking.  The Administrative Agent and the Borrower
hereby consent to the assignment made herein, and the Borrower undertakes within
five (5)  Business  Days from the  Assignment  Date to provide  new Notes to the
Administrative  Agent,  for the benefit of the  Assignee  and the  Assignor,  as
appropriate  to  reflect  the  portion  of the  Commitment  held  by each of the
Assignee and the Assignor after giving effect to the assignment  contemplated by
this Agreement. The Assignor agrees on the Business Day following receipt by the
Administrative  Agent of the new Note,  to  return  its  superseded  Note to the
Administrative  Agent,  which  shall  thereupon  transmit  the new  Notes to the
Assignor  and  the  Assignee  and  the  superseded  Note  to  the  Borrower  for
cancellation.

         3.  Representations  and  Warranties.  Each  of the  Assignor  and  the
Assignee  represents and warrants to the other, to the Administrative  Agent and
to the  Borrower  (a) that (i) it has full power and legal  right to execute and
deliver this Agreement and to perform the provisions of this Agreement; (ii) the
execution,  delivery,  and performance of this Agreement have been authorized by
all necessary action, corporate or otherwise, on its part and do not violate any
provisions  of  its  charter  or  by-laws  or  any  contractual  obligations  or
requirement  of law  binding  on it; and (iii) this  Agreement  constitutes  its
legal, valid and binding  obligation,  enforceable against it in accordance with
its  terms  subject,   as  to   enforcement   of  remedies,   to  the  following
qualifications:  (A) an order of  specific  performance  and an  injunction  are
discretionary  remedies and, in particular,  may not be available  where damages
are considered an adequate  remedy at law, and (B) enforcement may be limited by
bankruptcy, insolvency,  liquidation,  reorganization,  reconstruction and other
similar laws affecting  enforcement of creditors'  rights generally  (insofar as
any such law  relates to the  bankruptcy,  insolvency  or  similar  event of the
Assignee or the Assignor,  as the case may be), and (b) that its purchase of the
Assigned  Loans and the Assigned  Commitment  does not  constitute a "prohibited
transaction" as defined in Section 4.1(m) of the Loan Agreement.

         4.  Condition  Precedent.  The  obligations  of the  Assignor  and  the
Assignee hereunder shall be subject to the fulfillment of the condition that (i)
the Assignor shall have received  payment in full of the Purchase Price and (ii)
the  Assignor  and the  Assignee  shall  have  complied  with  other  applicable
provisions of Section 11.5(c) of the Loan Agreement.

         5.  Notice of  Assignment.  The  Assignor  hereby  gives  notice of the
assignment and  assumption of the Assigned Loans and the Assigned  Commitment to
the Administrative Agent and hereby


                                      - 2 -

<PAGE>



instructs the Borrower to make  payments with respect to the Assigned  Loans and
the Assigned Commitment directly to the Administrative  Agent for the benefit of
the  Assignee as provided in the Loan  Agreement;  provided,  however,  that the
Borrower  and the  Administrative  Agent  shall be  entitled to continue to deal
solely and  directly  with the  Assignor in  connection  with the  interests  so
assigned until (i) the  Administrative  Agent shall have received a copy of this
Assignment and Assumption Agreement duly executed by the Assignor, the Assignee,
and the  Borrower,  and shall have  received  the  assignment  fee  described in
Section  11.5(c)(iii)  of the Loan  Agreement,  and (ii) the Assignor shall have
delivered  to the  Administrative  Agent its Note.  From and after the date (the
"Effective Date") on which the  Administrative  Agent shall notify the Borrower,
the Assignee and the Assignor  that (i) and (ii) have  occurred and all consents
(if any) required have been given, the Assignee shall be deemed to be a party to
the Loan  Agreement  and, to the extent that rights and  obligations  thereunder
shall have been assigned to Assignee as provided  herein,  shall have the rights
and  obligations of a Bank under the Loan  Agreement.  After the Effective Date,
and with respect to all such amounts  accrued from the Assignment  Date, (a) all
interest,  principal, fees, and other amounts that would otherwise be payable to
the Assignor in respect of the Assigned Loans and the Assigned  Commitment shall
be paid to the Assignee,  (b) if the Assignor receives any payment on account of
the Assigned Loans or the Assigned  Commitment  that is payable to the Assignee,
the Assignor shall promptly deliver such payment to the Assignee, and (c) if the
Assignee  receives any payment in respect of Obligations of the Borrower accrued
prior to the Effective  Date,  then the Assignee  shall pay over the same to the
Assignor.  The Assignee agrees to deliver to the Borrower and the Administrative
Agent on or before the Effective Date such Internal Revenue Service forms as may
be required to establish that the Assignee is entitled to receive payments under
the Loan Agreement without deduction or withholding of tax.

         6.  Independent  Investigation.  The Assignee  acknowledges  that it is
purchasing  the  Assigned  Loans and the Assigned  Commitment  from the Assignor
without  recourse  and,  except as  provided  in Section  3(a)  hereof,  without
representation or warranty.  The Assignee further  acknowledges that it has made
its own  independent  investigation  and credit  evaluation  of the  Borrower in
connection  with its purchase of the Assigned Loans and the Assigned  Commitment
and has received copies of all Loan Documents that it has requested.  Except for
the  representations  or  warranties  set forth in Section  3(a),  the  Assignee
acknowledges  that it is not  relying on any  representation  or warranty of the
Assignor, expressed or implied, including without limitation, any representation
or warranty  relating to the legality,  validity,  genuineness,  enforceability,
collectibility,  interest  rate,  repayment  schedule,  or accrual status of the
Assigned Loans or the Assigned Commitment, the legality, validity,  genuineness,
or enforceability of the Loan Agreement,


                                      - 3 -

<PAGE>



the Notes, or any other Loan Document referred to in, or delivered  pursuant to,
the Loan  Agreement,  or the  financial  condition  or  creditworthiness  of the
Borrower.  The  Assignor  has not acted  and will not be  acting  as either  the
representative, agent or trustee of the Assignee with respect to matters arising
out of or relating to the Loan Agreement or this  Agreement.  From and after the
Effective Date, the Assignor shall have no rights or obligations with respect to
the Assigned Loans or the Assigned Commitment.

         7. Method of Payment.  All  payments to be made by the  Assignor or the
Assignee party  hereunder shall be in funds available at the place of payment on
the same day and shall be made by wire transfer to the account designated by the
party to receive payment.

         8.  Integration.  This Agreement shall supersede any prior agreement or
understanding  between the parties  (other than the Loan Agreement or other Loan
Documents) as to the subject matter hereof.

         9.  Counterparts.  This  Agreement  may be  executed  in any  number of
counterparts,  each of which  shall be  deemed  to be an  original  and shall be
binding upon the parties, their successors and assigns.

         10.  Governing Law. This Agreement  shall be governed by, and construed
in accordance  with,  the internal  laws of the State of New York  applicable to
contracts made and to be performed in New York.

         IN WITNESS WHEREOF, the Assignor and Assignee have executed, sealed and
delivered this Agreement as of the date first above written.

                                            [ASSIGNOR]



                                            By:

                                                 Title:


                                            [ASSIGNEE]



                                            By:

                                                 Title:


                                      - 4 -

<PAGE>




Agreed and Accepted:

AMERICAN TOWER SYSTEMS, INC.,
a Delaware corporation


By: _____________________________

Title :__________________________


Acknowledged:

TORONTO DOMINION (TEXAS), INC.,
as Administrative Agent


By: _____________________________

Title :__________________________


                                      - 5 -

<PAGE>



                                   SCHEDULE 1

                                       TO

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

                                 Loan Agreement
                        for American Tower Systems, Inc.
                          dated as of November 22, 1996


Item 1.           Assignor's Commitment:                      $__________


Item 2.           Assignor's Loans Outstanding

                  (a)      Base Rate Advances                 $__________

                  (b)      LIBOR Advances                     $__________


Item 3.           Amount of Assigned Commitment               $__________


Item 4.           Percentage of Commitment Assigned           __________%


Item 5.           Amount of Assigned Loans                    $__________

                  (a)      Base Rate Advances                 $__________

                  (b)      LIBOR Advances                     $__________


Item 6.           Lending Office of Assignee       _________________________
                  and Address for Notices          _________________________
                  under Loan Agreement             _________________________
                                                   _________________________


<PAGE>


                               Notes to Schedule 1


         1. Insert the dollar  amount of  Assignor's  portion of the  Commitment
prior to assignment.

         2. Insert the total amount of outstanding Loans of Assignor,  showing a
breakdown  by  type.  Description  of the  type of Loan  should  conform  to the
description in the Loan Agreement.

         3. Insert the dollar  amount of the  Assignor's  Commitment,  including
outstanding Loans, being assigned.

         4. Assigned  Commitment  as of a percentage of total  Commitment of all
Banks.

         5.  Insert the total  amount of  outstanding  Loans of  Assignor  being
assigned to Assignee. Description of the type of Loans should be consistent with
Item 2.

         6. Insert the name and address of the lending office of the Assignee.