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                                                                   Exhibit 10.26


                      SECOND AMENDMENT TO CREDIT AGREEMENT

         This SECOND AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered
into as of December 22, 1999, by and among SpectraSite  Communications,  Inc., a
Delaware corporation (the "Borrower"),  SpectraSite  Holdings,  Inc., a Delaware
corporation ("Holdco"),  CIBC World Markets Corp. (f/k/a CIBC Oppenheimer Corp.)
and Credit Suisse First Boston,  as arrangers (the  "Arrangers"),  Credit Suisse
First Boston, as syndication agent (the "Syndication Agent"),  Canadian Imperial
Bank of Commerce, as administrative agent (the "Administrative Agent"), Canadian
Imperial Bank of Commerce,  as collateral agent (the "Collateral Agent") and the
other Credit Parties signatory hereto (the "Credit Parties").

                              W I T N E S S E T H:

         WHEREAS,  the Borrower,  Holdco, the Arrangers,  the Syndication Agent,
the  Administrative  Agent,  the  Collateral  Agent and the Credit  Parties  are
parties to that certain Credit  Agreement dated as of April 20, 1999, as amended
by that certain First Amendment to Credit  Agreement dated as of August 23, 1999
(as the  same  may be  further  amended,  restated,  supplemented  or  otherwise
modified from time to time, the "Credit Agreement"); and

         WHEREAS, the Borrower and Holdco have requested, and the Arrangers, the
Syndication Agent, the Administrative Agent, the Collateral Agent and the Credit
Parties  have  agreed,  to amend the Credit  Agreement  as and to the extent set
forth  herein  and to waive  an  Event of  Default  existing  under  the  Credit
Agreement;

         NOW THEREFORE,  in  consideration  of the premises set forth above, the
terms and conditions contained herein and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree that all  capitalized  terms used herein shall have the meanings  ascribed
thereto in the Credit Agreement,  as amended hereby, except as otherwise defined
or limited  herein,  and further agree,  subject to the conditions  precedent to
this Amendment hereinafter set forth, as follows:

1.     Amendments to Article 1.

(a)ab Article 1 of the Credit  Agreement,  Definitions,  is hereby  modified and
amended by adding the  following  new  definitions  to be placed in  appropriate
alphabetical order:

                  "`Apex' shall mean Apex Site Management Holdings, Inc., a
Delaware corporation.

                  "`Apex  Acquisition'  shall  mean the  Acquisition  of Apex by
         Holdco  pursuant to the terms and  conditions  of the Apex  Acquisition
         Documents and the subsequent

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         transfer by Holdco to the Borrower of all of the issued and outstanding
         Capital Stock of Apex.

                  "`Apex  Acquisition  Documents' shall mean that certain Merger
         Agreement and Plan of Reorganization  dated as of November 24, 1999, as
         amended,  between the Borrower and Apex, and all schedules and exhibits
         thereto and documents executed in connection therewith.

                  "`Available  Cash' shall mean, on any  calculation  date,  the
         greater of (a) the amount of cash and cash  equivalents  on hand of the
         Borrower and its Subsidiaries minus $20,000,000, and (b) zero.

                  "`DigiPH' shall mean DigiPH PCS, Inc., an Alabama corporation.

                  "`DigiPH  Acquisition'  shall  mean  the  Acquisition  by  the
         Borrower of certain leases,  towers and related  facilities from DigiPH
         in conjunction with up to ninety-four (94) sites, and the related lease
         to DigiPH, under a master lease agreement,  of space on such towers and
         ground space on the land in the vicinity of such towers pursuant to the
         terms and conditions of the DigiPH Purchase Documents.

                  "DigiPH  Purchase  Documents'  shall mean that  certain  Asset
         Purchase  Agreement  dated as of November 5, 1999, as amended,  between
         the Borrower and DigiPH,  and all  schedules  and exhibits  thereto and
         documents executed in connection therewith.

                  "`Pre-Approved  Transactions'  shall mean,  collectively,  the
         Apex Acquisition,  the DigiPH Acquisition, the UbiquiTel Investment and
         the Acquisitions described in Section 8.5(xiii) hereof.

                  "`Pre-Approved     Transaction    Documents'    shall    mean,
         collectively,   the  Westower  Merger  Agreement,  the  NTA  Investment
         Documents,  the Apex Acquisition Documents,  DigiPH Purchase Documents,
         the UbiquiTel  Investment  Documents and the documents  relating to the
         Acquisitions  described  in Section  8.5(xiii)  hereof  (including  all
         schedules and exhibits thereto).

                  "`Second Amendment Date' shall mean December 22, 1999.

                  "`UbiquiTel' shall mean UbiquiTel Holdings, Inc., a Delaware
         corporation.

                  "`UbiquiTel  Investment"  shall  mean  the  Investment  by the
         Borrower  in  UbequiTel  pursuant  to the terms and  conditions  of the
         UbiquiTel Investment Documents in exchange for approximately twenty-six
         percent (26%) of the issued and outstanding equity of UbiquiTel.

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                  "`UbiquiTel  Investment  Documents'  shall  mean that  certain
         Series A Preferred  Stock Purchase  Agreement  dated as of November 23,
         1999,  as amended,  among the  Borrower,  UbiquiTel  and certain  other
         parties,  and all schedules and exhibits thereto and documents executed
         in connection therewith."

(b) Article 1 of the Credit Agreement, Definitions, is hereby further modified
and amended by deleting the existing definition of "Equity Offering".

(c) Article 1 of the Credit Agreement, Definitions, is hereby further modified
and amended by deleting  the  existing  definition  of  "Leverage  Ratio" and by
substituting the following in lieu thereof:

                  "`Leverage  Ratio' shall mean, on any  calculation  date,  the
         ratio  of (a)  Borrower  Debt,  to  (b)  Annualized  EBITDA;  provided,
         however, that at all times prior to the first anniversary of the Second
         Amendment Date, for purposes of determining  the Borrower's  compliance
         with Section 9.1 hereof (and not affecting the calculation of any other
         Financial  Covenant  or  the  determination  of the  Applicable  Margin
         pursuant to Section  2.3(g)  hereof),  "Leverage  Ratio" shall mean the
         ratio of (i) the greater of (A) (I) Borrower Debt, minus (II) Available
         Cash, and (B) zero, to (b) Annualized EBITDA."

2. Amendment to Section 2.1. Section 2.1 of the Credit  Agreement,  The Loans,
is hereby  modified and amended by deleting the first  sentence from  subsection
(f) and by substituting the following in lieu thereof:

                  "The  proceeds  of the Loans  shall be used (i) to finance the
         Nextel  Acquisition,   (ii)  to  finance  Permitted   Acquisitions  and
         Permitted  Investments,  (iii) to provide funding for the  acquisition,
         construction/development,  management and build-out of Towers and Tower
         Sites,  (iv)  for  general  corporate  purposes   (including,   without
         limitation,  fees and expenses relating to the Nextel Acquisition,  any
         Permitted   Acquisitions   and  any  Permitted   Investments   and  the
         transactions   contemplated  by  this  Agreement  and  the  other  Loan
         Documents),  and (v) for working  capital and other  general  corporate
         purposes."

3. Amendment to Section 2.7.  Section 2.7 of the Credit  Agreement,  Mandatory
Repayments,  is hereby modified and amended by deleting in its entirety existing
subsection (c) and by substituting the following in lieu thereof:

                  "(c) Debt Issuance. If, after the Agreement Date, Holdco shall
         conduct  any  public or  private  issuance  of any  Funded  Debt or any
         Convertible  Securities  (other  than the  issuance  of the Holdco 2009
         Notes  in  an  amount  not  to  exceed   $340,003,656)  (each  a  "Debt
         Offering"),  and the  Leverage  Ratio on a pro forma basis after giving
         effect to such Debt  Offering  shall be greater than 4.00 to 1.00,  the
         Borrower  shall  apply,  on the date of receipt of the Net  Proceeds of
         such Debt Offering by Holdco,  up to one hundred  percent (100%) of the
         Net Proceeds received by Holdco

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         with respect to such Debt Offering, to prepay the Senior Loans as set
         forth in Section 2.7(e)  hereof,  to the extent  necessary to cause the
         Leverage  Ratio to be less than or equal to 4.00 to 1.00 after giving
         effect to such Debt Offering."

4. Section 5.1(h) of the Credit Agreement, Title to Assets, is hereby modified
and amended by deleting the last  sentence  therefrom  and by  substituting  the
following in lieu thereof:

         "Tower Sub does not own any  material  Assets  other than Tower  Assets
         comprising the Nextel  Collateral and Tower Space Lease Agreements with
         Co-Locators on Towers comprising the Nextel Collateral, and Holdco does
         not own any  material  Assets  other than (i) the Capital  Stock of the
         Borrower,  (ii) the  Capital  Stock of any shell  Subsidiary  formed by
         Holdco   solely  for  the  purpose  of   consummating   any   Permitted
         Acquisition,   and  (iii)  on  the  closing   date  of  any   Permitted
         Acquisition,  the  Capital  Stock of any  target  company  acquired  in
         connection  with such Permitted  Acquisition  immediately  prior to the
         contribution of such Capital Stock to the Borrower."

5. Amendment to Section 6.2.  Section 6.2 of the Credit  Agreement,  Business;
Compliance with Applicable Law, is hereby amended by deleting the first sentence
therefrom and substituting the following in lieu thereof:

                   The Borrower  will,  and will cause each of its  Subsidiaries
         to,  engage solely in the business of the Tower  Operations,  the Other
         Operations  and in related  business  activities.  Holdco  will  engage
         solely  in the  business  of  holding  the  Capital  Stock  of (a)  the
         Borrower,  (b) any shell  Subsidiary  formed by Holdco  solely  for the
         purpose of  consummating  any Permitted  Acquisition,  and (iii) on the
         closing date of any Permitted Acquisition,  any target company acquired
         in connection with such Permitted Acquisition  immediately prior to the
         contribution of such Capital Stock to the Borrower."

6.  Amendment  to Section  6.9.  Section 6.9 of the Credit  Agreement,  Use of
Proceeds,  is hereby  amended by deleting the first  sentence  therefrom  and by
substituting the following in lieu thereof:

                   The Borrower will use the aggregate  proceeds of all Advances
         (a)  to  finance  the  Nextel  Acquisition,  (b) to  finance  Permitted
         Acquisitions and Permitted Investments,  (c) to provide funding for the
         acquisition,   construction/development  and  build-out  of  Towers  as
         permitted  hereunder,  (d) for general corporate  purposes  (including,
         without   limitation,   fees  and  expenses   relating  to  the  Nextel
         Acquisition,  any Permitted Acquisitions and any Permitted Investments,
         and the transactions  contemplated by this Agreement and the other Loan
         Documents),  and (e) for working  capital and other  general  corporate
         purposes."
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7.  Amendment to Section  7.1.  Section 7.1 of the Credit  Agreement,  Monthly
Financial  Statements  and  Information,  is  hereby  amended  by  deleting  the
reference  to  "thirty  (30)  days"  contained  therein  and by  replacing  such
reference with "forty-five (45) days".

8. Amendment to Section 8.4.  Section 8.4 of the Credit  Agreement,  Amendment
and Waiver,  is hereby deleted in its entirety and the following  substituted in
lieu thereof:

                  Section  8.4 Amendment  and  Waiver .  Neither  Holdco nor the
         Borrower shall,  and the Borrower shall cause each of its  Subsidiaries
         not to, without the prior written consent of the Arrangers,  enter into
         any  amendment  of, or agree to or accept any waiver  of,  which  would
         materially  adversely  affect the rights of the Borrower and the Credit
         Parties,  under  any of  them,  of any of the  provisions  of,  (a) its
         organizational   documents,    including,   without   limitation,   its
         certificate  or articles of  incorporation  (other than any increase in
         the  number  of  authorized   shares)  and  by-laws,   (b)  the  Nextel
         Acquisition  Documents,  (c)  the  Indentures,  (d) the  Holdco  Equity
         Documents, and (f) the Pre-Approved Transaction Documents."

9.     Amendments to Section 8.5.

(a) Section 8.5 of the Credit Agreement,  Liquidation;  Merger; Acquisition or
Disposition  of Assets,  is hereby  modified  and amended by  deleting  existing
subsection (vii) and substituting the following in lieu thereof:

                  "(vii)  subject to  compliance  with  Section 6.10 and Section
         6.16 hereof,  the Borrower and its Subsidiaries  (other than Tower Sub)
         may make  Acquisitions  and  Investments  (including the acquisition of
         Capital  Stock  or  other  equity   interests  in  Persons  engaged  in
         businesses  similar to the Tower Operations) and form Subsidiaries with
         respect thereto, subject to the following conditions:

                           "(A)     no  Default  or Event of  Default  shall
then  exist  before  or after  giving  effect to any such Acquisition or
Investment;

                           "(B)  the  Purchase   Price  with  respect  any  such
                  Acquisition  or  Investment  shall be (I)  payable  solely  in
                  common stock of Holdco, or (II) payable in cash so long as (x)
                  the cash  portion of the  Purchase  Price with  respect to any
                  single  Acquisition  or  Investment  (with respect to a single
                  transaction  or a series of  related  transactions)  shall not
                  exceed $50,000,000,  and (y) the aggregate cash portion of the
                  Purchase Price for  Acquisitions  and Investments  consummated
                  pursuant to this clause (vii) (other than the  Acquisition  of
                  the Future  Nextel  Towers)  during the period from the Second
                  Amendment Date through the Tranche B Maturity Date,  shall not
                  exceed $200,000,000;

                           "(C) with respect to Acquisitions structured as Tower
                  Asset  exchanges or swaps,  the following  restrictions  shall
                  apply:   (x)  the  cash  outlay

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                  by  the   Borrower  for  such Acquisition must be within the
                  dollar limitations set forth in the   preceding   clause  (B);
                  (y)  the   Annualized   EBITDA attributable  to the  Tower
                  Assets  being  acquired  must  be substantially similar to or
                  greater than the Annualized EBITDA of the Tower Assets being
                  exchanged or swapped; and (z) if the exchange  involves  more
                  than  twenty-five  (25)  Towers,  the Towers  acquired  in
                  such  transaction  must have as an anchor tenant a Nextel
                  Tenant or another tenant reasonably acceptable to the Majority
                  Lenders.

                           "(D) the Borrower  shall provide to the Arrangers and
                  the Lenders  calculations  demonstrating  pro forma compliance
                  with the  Financial  Covenants  after  giving  effect  to such
                  Acquisition or Investment; and

                           "(E)  with  respect  to  any  Acquisition  having  an
                  aggregate Purchase Price (with respect to a single transaction
                  or a series of related transactions) in excess of $20,000,000,
                  the Borrower  shall  provide to the  Arrangers and the Lenders
                  revised Projections  assuming  consummation of the Acquisition
                  and  demonstrating  pro forma  compliance  with the  Financial
                  Covenants through the Tranche B Maturity Date;"

(b) Section 8.5 of the Credit Agreement,  Liquidation;  Merger; Acquisition or
Disposition  of Assets,  is hereby  further  modified  and amended by adding the
following new subsections (xii) and (xiii) at the end thereof:

                  "(xii) so long as no Default or Event of Default  then  exists
         or would be caused  thereby,  the Borrower may  consummate  each of the
         Pre-Approved  Transactions  (other than the  transaction  described  in
         clause (xiii) below); and

                  (xiii)  so long as (A) no  Default  or Event of  Default  then
         exists or would be caused  thereby and (B) the Borrower  shall  provide
         the  Arrangers  with  evidence  satisfactory  to each of them  that the
         revenue and cash flow acquired by the Borrower in connection  with each
         such Acquisition  shall have no material  negative  deviations from the
         projected   revenue  and  cash  flow   relating  to   broadcast   tower
         Acquisitions as set forth in the Borrower's Projections with respect to
         such  Acquisitions  dated  December  1999, the Borrower may make one or
         more  Acquisitions  of broadcast  towers,  or of Persons engaged in the
         broadcast   tower   business,   on  terms  and  conditions   reasonably
         satisfactory  to the Arrangers and having an aggregate  Purchase Price,
         for all such Acquisitions, not to exceed $70,000,000 (inclusive of cash
         and stock consideration)."

10. Amendment to Section 8.7. Section 8.7 of the Credit Agreement,  Restricted
Payments and Purchases, is hereby amended by adding the following new subsection
(g) to the end thereof:

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                   (g) on the  date on  which  the  Apex  Acquisition  shall  be
         consummated,  repayment  of any  existing  Indebtedness  of  Apex in an
         aggregate amount not to exceed $3,000,000."

11. Amendment to Section 8.9. Section 8.9 of the Credit  Agreement,  Corporate
Name;  Corporate Structure;  Business,  is hereby amended by deleting subsection
(b) therefrom and by substituting the following in lieu thereof:

                   (b) with respect to the Borrower and its Subsidiaries, engage
         in any  businesses  other  than  the  Tower  Operations  and the  Other
         Operations and activities related or incident thereto, and with respect
         to  Holdco,  engage in any  business  other  than that of  holding  the
         Capital Stock of (i) the Borrower,  (ii) any shell Subsidiary formed by
         Holdco   solely  for  the  purpose  of   consummating   any   Permitted
         Acquisition,   and  (iii)  on  the  closing   date  of  any   Permitted
         Acquisition,  any  target  company  acquired  in  connection  with such
         Permitted  Acquisition  immediately  prior to the  contribution of such
         Capital Stock to the Borrower"

12.  Waiver.  Pursuant to Section 4.5 of the Credit  Agreement,  the  Borrower
agreed to deliver to the Arrangers a duly executed landlord waiver agreement, in
form and substance satisfactory to the Arrangers and their counsel, with respect
to the  Borrower's  principal  place of  business  and the  Borrower's  premises
located at One Chase Corporate Drive,  Hoover,  Alabama,  on or before September
30, 1999 (such landlord waiver agreements being  hereinafter  referred to as the
"Required  Landlord  Waivers").  As of the date  hereof,  the  Borrower  has not
delivered  the  required  landlord  waiver  agreements  to  the  Arrangers  (the
"Landlord  Waiver  Default").   The  Arrangers,   the  Syndication   Agent,  the
Administrative  Agent,  the Collateral Agent and the Credit Parties hereby waive
the Landlord Waiver Default  existing as of the date hereof and hereby waive the
requirement  of  Section  4.5 that the  Borrower  deliver to the  Arrangers  the
Required  Landlord Waivers.  The waivers set forth in the immediately  preceding
sentence shall not waive any other requirement or hinder,  restrict or otherwise
modify the rights and remedies of the  Arrangers,  the  Syndication  Agent,  the
Administrative  Agent, the Collateral Agent and the Credit Parties following the
occurrence of any Default or Event of Default under the Credit Agreement.

13. No Other  Amendments,  Waivers or  Consents.  Except  for the  amendments,
waivers and consents set forth above,  the text of the Credit  Agreement and the
other Loan Documents  shall remain  unchanged and in full force and effect,  and
the Arrangers,  the Syndication Agent, the Administrative  Agent, the Collateral
Agent  and the  Credit  Parties  hereby  reserve  the  right to  require  strict
compliance with the terms of the Credit  Agreement and the other Loan Documents,
including,  without  limitation,  all terms  applicable to  Subsidiaries  of the
Borrower, in the future.

14.  Conditions  Subsequent.  As a  condition  subsequent  to the  amendments,
waivers and consents set forth in this Amendment,  the Borrower shall perform or
cause to be performed the  following  (the failure by the Borrower to so perform
or  cause  to be  performed  for

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any  reason  (other  than  the  fact  that  the Pre-Approved   Transaction  to
which  such  condition   relates  was  not  ever consummated) constituting an
Event of Default under the Credit Agreement):

(a)      Collateral.   On  the  closing  date  for  each  of  the   Pre-Approved
         Transactions, the Borrower shall execute and deliver, or as applicable,
         cause its Subsidiaries to execute and deliver,  to the Collateral Agent
         all agreements, instruments and other items required to be so delivered
         pursuant to Section 6.16 of the Credit Agreement.

(b)      Definitive  Documentation.  Promptly  upon the  closing  of each of the
         Pre-Approved Transactions,  the Borrower shall deliver to the Arrangers
         a full set of copies of the documents  executed in connection with such
         Pre-Approved Transaction.

15. Conditions to  Effectiveness.  This Amendment shall be effective as of the
date first written above (the "Effective Date") upon the following:

                  (a) the Administrative Agent's receipt of a counterpart hereof
 duly executed by the Borrower and Holdco, and by the Majority Lenders;

                  (b) with respect to each of the Pre-Approved Transactions, the
         Arrangers'  receipt  of  (i)  updated   Projections  for  the  Borrower
         demonstrating  the Borrower's pro forma  compliance  with the Financial
         Covenants after giving effect thereto,  and (ii) copies of any material
         agreements relating to such Pre-Approved  Transaction in the possession
         of the Borrower; and

                  (c) the  representations  and  warranties  of  Holdco  and the
         Borrower set forth in the Credit  Agreement and this  Amendment,  other
         than those that are expressly  made as of a specific date, are true and
         correct in all  material  respects  with the same effect as though such
         representations and warranties had been made on and as of the Effective
         Date.

16.  Representations  and  Warranties.  Each of the Borrower  and Holdco,  for
itself  and on  behalf  of  each of its  Subsidiaries,  agrees,  represents  and
warrants in favor of the Arrangers,  the Syndication  Agent, the  Administrative
Agent, the Collateral Agent and the Credit Parties that:

(a)      This  Amendment  has been  executed and  delivered  by duly  authorized
         representatives  of the Borrower and Holdco,  and the Credit Agreement,
         as modified and amended by this Amendment,  constitutes a legal,  valid
         and binding  obligation  of the Borrower and Holdco and is  enforceable
         against the Borrower and Holdco in accordance with its terms, except as
         enforceability may be limited by bankruptcy, insolvency, reorganization
         or  similar  laws  affecting  creditors'  rights  generally  and by the
         application of general equitable principles;

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(b)      Before and after giving effect to this  Amendment,  no Default or Event
         of Default  with  respect to the  Borrower  or Holdco  (other  than the
         Defaults  and Events of  Default  described  in Section 12 hereof)  has
         occurred and is continuing;

(c)      As of  the  date  hereof  and  after  giving  effect  to  each  of  the
         Pre-Approved Transactions,  (i) the property of the Borrower, at a fair
         valuation  on a going  concern  basis,  will exceed its debt;  (ii) the
         capital of the Borrower will not be  unreasonably  small to conduct its
         business;  and (iii) the Borrower will not have incurred debts, or have
         intended to incur  debts,  beyond its ability to pay such debts as they
         mature;

(d)      No  event  contemplated  in  connection  with  any of the  Pre-Approved
         Transactions  shall occur,  which has not been  consented to or waived,
         the  occurrence  of which  constitutes,  or with the passage of time or
         giving  of notice or both  would  constitute,  a  material  default  by
         Holdco, the Borrower or any of their respective  Subsidiaries under any
         material indenture,  agreement or other instrument,  including, without
         limitation,  the material Necessary  Authorizations and the Indentures,
         or any judgment,  decree or order, to which Holdco, the Borrower or any
         of their  respective  Subsidiaries  is a party or by which Holdco,  the
         Borrower  or any  of  their  respective  Subsidiaries  or any of  their
         respective properties may be bound or affected; and

(e)      All of the  representations  and  warranties of Holdco and the Borrower
         contained  in the Credit  Agreement  (other  than  representations  and
         warranties  that relate solely to a specified date) continue to be true
         and  correct in all  material  respects as of the date hereof as though
         made on and as of such date.

17. Effect on the Credit  Agreement.  Except as specifically  provided herein,
the  Credit  Agreement  shall  remain in full  force and  effect,  and is hereby
ratified,  reaffirmed and confirmed. This Amendment shall be deemed to be a Loan
Document for all purposes.

18.  Counterparts.  This  Amendment  may be executed in any number of separate
counterparts and by the different parties hereto on separate counterparts,  each
of which shall be deemed an original and all of which, taken together,  shall be
deemed to constitute one and the same  instrument.  In proving this Amendment in
any  judicial  proceedings,  it shall not be necessary to produce or account for
more than one such counterpart signed by the party against whom such enforcement
is sought. Any signatures  delivered by a party by facsimile  transmission shall
be deemed an original signature hereto.

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19. Law of Contract.  THIS CONSENT 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 WHOLLY WITHIN SUCH STATE.



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                                       10

<PAGE>   11



SECOND AMENDMENT (SPECTRASITE COMMUNICATIONS, INC.)
         IN WITNESS WHEREOF, this Amendment has been duly executed as of the day
and year first written above.

BORROWER:                   SPECTRASITE COMMUNICATIONS, INC.


                                    By:              /s/  David P. Tomick
                                                     ---------------------------
                                    Name:            David P. Tomick
                                    Title:           Executive Vice President



                                    Attest:
                                            Name:
                                            Title:


HOLDCO:                    SPECTRASITE HOLDINGS, INC.


                                    By:              /s/  David P. Tomick
                                                     ---------------------------
                                    Name:            David P. Tomick
                                    Title:           Executive Vice President



                                    Attest:
                                    Name:
                                    Title:





<PAGE>   12



ADMINISTRATIVE
AGENT:                              CANADIAN IMPERIAL BANK OF COMMERCE


                                    By:              /s/  Colleen Risorto
                                                     ---------------------------
                                    Name:            Colleen Risorto
                                    Title:           Executive Director
                        CIBC World Markets Corp. As Agent




<PAGE>   13



ARRANGERS:                          CIBC WORLD MARKETS CORP.
                                    (f/k/a CIBC Oppenheimer Corp.)


                                    By:              /s/  Colleen Risorto
                                                     ---------------------------
                                    Name:            Colleen Risorto
                                    Title:           Executive Director
                        CIBC World Markets Corp. As Agent

                                    CREDIT SUISSE FIRST BOSTON


                                    By:              /s/  Jeffrey B. Ulmer
                                                     ---------------------------
                                    Name:            Jeffrey B. Ulmer
                                    Title:           Vice President

                                    By:              /s/ Douglas E. Maher
                                                     ---------------------------
                                    Name:            Douglas E. Maher
                                    Title:           Vice President





<PAGE>   14



COLLATERAL AGENT: CANADIAN IMPERIAL BANK OF COMMERCE



                                    By:              /s/  Colleen Risorto
                                                     ---------------------------
                                    Name:            Colleen Risorto
                                    Title:           Executive Director
                        CIBC World Markets Corp. As Agent





<PAGE>   15



SYNDICATION AGENT:         CREDIT SUISSE FIRST BOSTON


                                    By:              /s/  Jeffrey B. Ulmer
                                                     ---------------------------
                                    Name:            Jeffrey B. Ulmer
                                    Title:           Vice President

                                    By:              /s/  Douglas E. Maher
                                                     ---------------------------
                                    Name:            Douglas E. Maher
                                    Title:           Vice President





<PAGE>   16



MANAGING AGENTS:           BANK OF MONTREAL, CHICAGO BRANCH


                                    By:             /s/  Karen Klapper
                                                    ----------------------------
                                    Name:            Karen Klapper
                                    Title:           Director


                                    THE BANK OF NOVA SCOTIA


                                    By:         /s/  Vincent J. Fitzgerald, Jr.
                                                --------------------------------
                                    Name:            Vincent J. Fitzgerald, Jr.
                                    Title:           Authorized Signatory


                                    FLEET NATIONAL BANK (f/k/a BankBoston, N.A.)


                                    By:              /s/  Shepard D. Rainie
                                                     ---------------------------
                                    Name:            Shepard D. Rainie
                                    Title:           Managing Director


                           DRESDNER BANK AG, NEW YORK AND GRAND CAYMAN BRANCHES


                                    By:             /s/  Patrick A. Keleher
                                                    ----------------------------
                                    Name:            Patrick A. Keleher
                                    Title:           Vice President


                                    By:             /s/  Brian E. Haughney
                                                    ----------------------------
                                    Name:            Brian E. Haughney
                                    Title:           Assistant Vice President


                                    TORONTO DOMINION (TEXAS), INC.


                                    By:             /s/  Sheila M. Conley
                                                    ----------------------------
                                    Name:            Sheila M. Conley
                                    Title:           Vice President

                                    UNION BANK OF CALIFORNIA, N.A.


                                    By:             /s/  Peter C. Connoy
                                                    ----------------------------
                                    Name:            Peter C. Connoy
                                    Title:           Vice President





<PAGE>   17



CO-AGENT:                           CREDIT LYONNAIS NEW YORK BRANCH


                                    By:             /s/  Mark A. Campellone
                                                    ----------------------------
                                    Name:            Mark A. Campellone
                                    Title:           First Vice President





<PAGE>   18



LENDERS:                   CIBC INC.


                                    By:              /s/  Colleen Risorto
                                                     ---------------------------
                                    Name:            Colleen Risorto
                                    Title:           Executive Director
                        CIBC World Markets Corp. As Agent





<PAGE>   19



                                    CREDIT SUISSE FIRST BOSTON


                                    By:              /s/  Jeffrey B. Ulmer
                                                     ---------------------------
                                    Name:            Jeffrey B. Ulmer
                                    Title:           Vice President


                                    By:              /s/  Douglas E. Maher
                                                     ---------------------------
                                    Name:            Douglas E. Maher
                                    Title:           Vice President





<PAGE>   20



                                    BANK OF MONTREAL, CHICAGO BRANCH


                                    By:             /s/  Karen Klapper
                                                    ----------------------------
                                    Name:            Karen Klapper
                                    Title:           Director




<PAGE>   21



                                    THE BANK OF NOVA SCOTIA


                                    By:          /s/  Vincent J. Fitzgerald, Jr.
                                                 -------------------------------
                                    Name:             Vincent J. Fitzgerald, Jr.
                                    Title:           Authorized Signatory





<PAGE>   22



                                    FLEET NATIONAL BANK (f/k/a BankBoston, N.A.)


                                    By:              /s/  Shepard D. Rainie
                                                     ---------------------------
                                    Name:                 Shepard D. Rainie
                                    Title:                Managing Director




<PAGE>   23



                            DRESDNER BANK AG, NEW YORK AND GRAND CAYMAN BRANCHES


                                    By:              /s/  Patrick A. Keleher
                                                     ---------------------------
                                    Name:            Patrick A. Keleher
                                    Title:           Vice President


                                    By:              /s/  Brian E. Haughney
                                                     ---------------------------
                                    Name:            Brian E. Haughney
                                    Title:           Assistant Vice President




<PAGE>   24



                                    TORONTO DOMINION (TEXAS), INC.


                                    By:              /s/  Sheila M. Conley
                                                     ---------------------------
                                    Name:            Sheila M. Conley
                                    Title:           Vice President





<PAGE>   25



                                    UNION BANK OF CALIFORNIA, N.A.


                                    By:              /s/  Peter C. Connoy
                                                     ---------------------------
                                    Name:            Peter C. Connoy
                                    Title:           Vice President





<PAGE>   26



                                    CREDIT LYONNAIS NEW YORK BRANCH


                                    By:              /s/  Mark A. Campellone
                                                     ---------------------------
                                    Name:            Mark A. Campellone
                                    Title:           First Vice President





<PAGE>   27



                                    THE BANK OF NEW YORK


                                    By:              /s/  Gerry Granovsky
                                                     ---------------------------
                                    Name:            Gerry Granovsky
                                    Title:           Vice President





<PAGE>   28



                                    CAISSE DE DEPOT ET PLACEMENT DU QUEBEC


                                    By:              /s/  Louis Lavoie
                                                     ---------------------------
                                    Name:            Louis Lavoie
                                    Title:           Manager


                                    By:              /s/  Lucie Rousseau
                                                     ---------------------------
                                    Name:            Lucie Rousseau
                                    Title:           Vice President





<PAGE>   29



                                    CANADIAN IMPERIAL BANK OF COMMERCE


                                    By:              /s/  Colleen Risorto
                                                     ---------------------------
                                    Name:            Colleen Risorto
                                    Title:           Executive Director
                        CIBC World Markets Corp. As Agent




<PAGE>   30



                                    THE CIT GROUP/EQUIPMENT FINANCING, INC.


                                    By:             /s/  Daniel E. A. Nichols
                                                    ----------------------------
                                    Name:            Daniel E. A. Nichols
                                    Title:           Assistant Vice President





<PAGE>   31



                                    CYPRESSTREE INVESTMENT FUND, LLC

                       By:     CypressTree Investment Management Company, Inc.,
                               its Managing Member


                                    By:
                                    Name:
                                    Title:





<PAGE>   32



                                    NORTHAMERICAN SENIOR FLOATING RATE FUND

                       By:     CypressTree Investment Management Company, Inc.,
                               its Managing Member


                                    By:
                                    Name:
                                    Title:




<PAGE>   33



                                 CYPRESSTREE INVESTMENT MANAGEMENT COMPANY, INC.

                       As:     Attorney-in-Fact and on behalf of First Allmerica
                               Financial Life Insurance Company as Portfolio
                               Manager


                                    By:
                                    Name:
                                    Title:





<PAGE>   34



                                    KZH CYPRESSTREE-1 LLC


                                    By:              /s/  Peter Chin
                                                     ---------------------------
                                    Name:            Peter Chin
                                    Title:           Authorized Agent





<PAGE>   35



                                    FREMONT INVESTMENT & LOAN


                                    By:
                                    Name:
                                    Title:





<PAGE>   36



                                    HELLER FINANCIAL, INC.


                                    By:              /s/  Scott Ziemke
                                                     ---------------------------
                                    Name:            Scott Ziemke
                                    Title:           Assistant Vice President





<PAGE>   37



                                    MERRILL LYNCH SENIOR FLOATING RATE
                                    FUND, INC.


                                    By:
                                    Name:
                                    Title:





<PAGE>   38



                   PPM AMERICA, INC., as attorney in fact, on behalf of Jackson
                   National Life Insurance Company


                                    By:
                                    Name:
                                    Title:





<PAGE>   39



                 Fleet   National  Bank  (f/k/a   BankBoston, N.A.), as Trust
                 Administrator for LONGLANE MASTER TRUST IV


                                    By:
                                    Name:
                                    Title:





<PAGE>   40



                                    GALAXY CLO 1999-1, LTD.

                    By:     SAI Investment Advisor, Inc., its Collateral Manager


                                    By:
                                    Name:
                                    Title:





<PAGE>   41



                                    OXFORD STRATEGIC INCOME FUND

                           By:     Eaton Vance Management, as Investment Advisor


                                    By:              /s/  Scott H. Page
                                                     ---------------------------
                                    Name:            Scott H. Page
                                    Title:           Vice President





<PAGE>   42



                                    SENIOR DEBT PORTFOLIO

                   By:     Boston Management and Research, as Investment Advisor


                                    By:              /s/ Scott H. Page
                                                     ---------------------------
                                    Name:            Scott H. Page
                                    Title:           Vice President





<PAGE>   43



                                    J.H. WHITNEY MARKET VALUE FUND, L.P.

                        By:     J.H. Whitney Value GP, Ltd., its General Partner


                                    By:
                                    Name:
                                    Title:





<PAGE>   44



                                    J.H. WHITNEY MEZZANINE FUND, L.P.

                               By:           Whitney GP, Ltd. - General Partner
                                             -----------------------------------


                                    By:              /s/  Daniel J. O'Brien
                                                     ---------------------------
                                    Name:            Daniel J. O'Brien
                                    Title:           Managing Member





<PAGE>   45



                                    BANK OF AMERICA, N.A.


                                    By:
                                    Name:
                                    Title:





<PAGE>   46



                                    DEBT STRATEGIES FUND II, INC.


                                    By:
                                    Name:
                                    Title:




<PAGE>   47



                                    DEBT STRATEGIES FUND III, INC.


                                    By:
                                    Name:
                                    Title:





<PAGE>   48



                                    THE FUJI BANK, LIMITED, NEW YORK BRANCH


                                    By:
                                    Name:
                                    Title:





<PAGE>   49



                                    VAN KAMPEN SENIOR INCOME TRUST


                                    By:            /s/  Darvin D. Pierce
                                                   -----------------------------
                                    Name:          Darvin D. Pierce
                                    Title:           Vice President





<PAGE>   50



                                    PROSPECT INTERNATIONAL DEBT
                                    STRATEGY FUND


                                    By:
                                    Name:
                                    Title:





<PAGE>   51



                                    CARAVELLE INVESTMENT FUND L.L.C.


                                    By:              /s/  Dean T. Criares
                                                     ---------------------------
                                    Name:            Dean T. Criares
                                    Title:           Managing Director




<PAGE>   52



                                    EATON VANCE SENIOR INCOME TRUST


                                    By:              /s/  Scott H. Page
                                                     ---------------------------
                                    Name:            Scott H. Page
                                    Title:           Vice Presisdent




<PAGE>   53



                                    MERRILL LYNCH SENIOR FLOATING RATE
                                    FUND    II, INC.


                                    By:
                                    Name:
                                    Title:




<PAGE>   54



                                     MORGAN STANLEY DEAN WITTER PRIME
                                    INCOME TRUST


                                    By:
                                    Name:
                                    Title:




<PAGE>   55



                                    ELC "Cayman" Ltd. 1999-III


                                    By:              /s/  Thomas M.Finke
                                                     ---------------------------
                                    Name:            Thomas M. Finke
                                    Title:           Managing Director