* IMPORTANT NOTE:  CERTAIN  MATERIAL,  INDICATED BY AN ASTERISK ("*"),  HAS BEEN
OMITTED FROM THIS DOCUMENT PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT.

Execution Copy

# FIRST
AMENDMENT AGREEMENT

THIS FIRST AMENDMENT AGREEMENT (this "Amendment"), dated as of February 26, 2001, is made
between Pathnet Operating, Inc., a Delaware corporation ("Borrower") and Cisco Systems Capital Corporation , a
Nevada corporation ("Lender").

Borrower and Lender are parties to an Agreement dated as of September 7, 2000 (the "Credit
Agreement").  Borrower has requested that Lender provide certain additional financing constituting Eligible
Secured Debt.  Lender has agreed to such request, subject to the terms and conditions hereof.

Accordingly, the parties hereto agree as follows:

SECTION 1         Definitions; Interpretation.

(a)        Terms Defined in Credit Agreement.  All capitalized terms used in this Amendment (including in the
recitals hereof) and not otherwise defined herein shall have the meanings assigned to them in the Credit
Agreement.

(b)        Interpretation.  The rules of interpretation set forth in Section 1.2 of the Credit Agreement shall be
applicable to this Amendment and are incorporated herein by this reference.

SECTION 2          Amendments to the Credit Agreement.

(a) Amendments. The
Credit Agreement shall be amended as follows, effective as of the date of
satisfaction of the conditions set forth in Section 4 (the Effective
Date):

(i)              The preamble to the Credit Agreement is hereby amended by replacing the
reference therein to "$50,000,000" with a reference to "$95,000,000".

(ii)             Section 1.1 of the Credit Agreement is hereby amended by adding the following
definition thereto in alphabetical order:

"Availability Period" has the meaning set forth in the Schedule."

"First Amendment Effective Date" means the "Effective Date" as that terms in defined

in that certain First Amendment Agreement dated as of February 26, 2001 between Borrower and
Lender.

(iii)    The preamble to the Schedule is hereby amended by striking the reference to
"Pathnet Telecommunications, Inc." contained therein.

(iv)     Section 1(a) of the Schedule is hereby amended by deleting current Section
1(a) in its entirety and replacing such Section with the following:

"(a)     Availability Period:

(i) Up to $60,000,000 ("Tranche A") shall be available from the Closing Date through
the second anniversary of the Closing Date (the "Commitment Expiry Date").

(ii) Up to $10,000,000 ("Tranche B") shall be available from the Closing Date through
the Commitment Expiry Date.

(iii) Up to $25,000,000 shall be available as follows: (A) $8,500,000 from February
28, 2001 through March 31,
2001 (Tranche C1) and (B) $16,500,000 from the First Amendment
Effective Date through the Commitment Expiry Date (Tranche C2)
(Tranche C1 and Tranche C2 shall be collectively referred to as Tranche
C).

A tranche becomes available hereunder on the first Banking Day that Loans under such tranche
are available to the Borrower under this Section 1(a).  The period from the Closing Date through the Commitment
Expiry Date shall be referred to herein as the "Availability Period"."

(v)      Section 1(c) of the Schedule is hereby amended by deleting the reference to
"$50,000,000" contained therein and replacing such reference with a reference to "$95,000,000".

(vi)     Section 1(g) of the Schedule is hereby amended by adding a new Section
1(g)(iii) to read in full as follows:

"(iii)   Conditions Precedent to Additional Loans:The following conditions precedent
shall be satisfied on or
prior to each borrowing of Additional Loans: (A) no Default or
Event of Default (as such terms are defined in the Financing
Documents) shall have occurred and be continuing under the Financing Documents
on the date of such borrowing and (B) Borrower shall be in compliance with each
of the financial covenants set forth in the Financing Documents determined on a
pro forma basis as of the last day of the most recently ended fiscal quarter of
Borrower for which financial statements are available as though the relevant
borrowing of Additional Loans had been incurred on the last day of such fiscal
quarter for testing compliance with each such covenant before and after the
effect of such incurrence.

For purposes of this Section 1(g)(iii), the term "Additional Loans" shall mean each of
the following:  (A) the last $20,000,000 of Loans under Tranche A and (B) all Loans under Tranche C.

(iv)    Conditions Precedent to Tranche C1:  The following conditions precedent shall
be satisfied on or prior to
the borrowing under Tranche C1: (A) Borrower shall have presented evidence in
form and substance reasonably satisfactory to Lender that Holdings and/or PNI
have retained an advisor to assist in the restructuring of the PNI Senior Notes
and that Holdings and/or PNI have held at least one meeting with representatives
of a significant portion of the holders of the PNI Senior Notes to discuss a
restructuring of such notes, (B) Borrower shall have presented evidence in form
and substance reasonably satisfactory to Lender that Holdings or Borrower has
held at least one meeting with a credible equity source and (C) Borrower shall
present evidence in form and substance reasonably satisfactory to Lender that it
will have a pro forma positive cash balance for the month of February, 2001
after giving effect to the borrowing under Tranche C1.

(v)     Conditions Precedent to Tranche C2: (A) The following conditions precedent
shall be satisfied on or
prior to the first borrowing of Loans under Tranche C2: (1) Holdings and PNI
shall have completed a restructuring of the PNI Senior Notes in form and
substance reasonably satisfactory to Lender, (2) Borrower shall have received at
least $100,000,000 in cash equity on or after the First Amendment Effective Date
from one or more equity investors (whether directly from such equity investors
or indirectly as an equity contribution from Holdings) and (3) Borrower shall
have paid an availability fee in the amount of * to Lender. (B) In
addition, prior to each borrowing of Loans under Tranche C2, Borrower shall
present evidence in form and substance reasonably satisfactory to Lender that it
will have a pro forma positive cash balance during any month in which a
borrowing under Tranche C2 occurs after giving effect to all borrowings under
Tranche C2 for such month (including the borrowing for which such evidence is
presented).

(vii)    Section 2(a) of the Schedule is hereby amended by deleting the current Section
2(a) in its entirety and replacing such Section with the following:

"(a) Use of Proceeds: Up to $60,000,000 under Tranche A for the financing of
Borrowers purchase of
Cisco Systems networking and telecommunications equipment and services from the
Vendor thereof; provided that proceeds from Loans made under Tranche A
may be used for the financing of Cisco Systems networking and telecommunications
equipment and services purchased by Borrower on or after April 24, 2000;
provided, further, that with respect to the last $20,000,000 of
availability under Tranche A, such Cisco Systems networking and
telecommunications equipment and services shall be purchased only from Cisco
Systems and only $3,000,000 shall be used to purchase Cisco Systems networking
and telecommunications services without the Lenders prior written consent;
up to $10,000,000 under Tranche B for the financing of any costs incurred by the
Borrower for hardware or other goods and services associated with the
integration and installation of Cisco Systems networking and telecommunications
equipment, but excluding any such costs for hardware, goods or services payable
to direct competitors of Cisco Systems; up to $25,000,000 under Tranche C for
the financing of Borrowers acquisition, construction, installation or
improvement of capital assets that constitute part of the Collateral;
provided that the use of proceeds under Tranche C to finance any such
acquisition, construction, installation or improvement shall occur within 270
days of such purchase, construction, installation or improvement, and shall not
exceed 100% of the aggregate cost of such acquisition, construction,
installation or improvement.

(viii)   Section 2(b) of the Schedule is hereby amended by deleting the current Section
2(b) in its entirety and replacing such Section with the following:

"(b) Note(s):  Amended and Restated Promissory Note in substantially the form of
Exhibit C evidencing
the Loans under Tranche A (the Tranche A Loans); Promissory Note in
the form of Exhibit D, evidencing the Loans under Tranche B (the
Tranche B Loans); and Promissory Note in the form of
Exhibit F, evidencing the Loans under Tranche C (the Tranche C
Loans).

(ix)     Section 2(c) of the Schedule is hereby amended by deleting the third paragraph
thereto in its entirety and replacing such third paragraph with the following:

"Except to the extent that any such prepayment is required to be applied to a
particular tranche, any
such amounts received as a mandatory prepayment of the Loans shall be applied
first to the Tranche C Loans, second to the Tranche B Loans and third to the
Tranche A Loans.

(x)      Exhibit C to the Credit Agreement is hereby deleted in its entirety and
replaced with Exhibit A hereto.

(xi)     A new Exhibit F shall be added to the Credit Agreement in substantially the
form of Exhibit B hereto.

(b) References Within
Credit Agreement. Each reference in the Credit Agreement to this
Agreement and the words hereof, herein,
hereunder, or words of like import, shall mean and be a reference to
the Credit Agreement as amended by this Amendment.

SECTION 3             Fees.  Borrower shall pay an amendment fee of "*" payable on the date of
              this Amendment.  Such amendment fee shall be fully earned upon becoming due and payable, shall be non-refundable
for any reason whatsoever and shall be in addition to any other fee, cost or expense payable pursuant to the
Credit Agreement.

SECTION 4 Conditions of
Effectiveness. The effectiveness of Section 2 of this Amendment shall be
subject to the satisfaction of each of the following conditions precedent:

(a) Fees and
Expenses. Borrower shall have paid (i) all fees then due in accordance
with Section 3 and (ii) all invoiced costs and expenses then due in
accordance with Section 6(c).

(b)      Closing Documents.  Lender shall have received the following additional Loan Documents and consents, in

form and substance satisfactory to it:

(i)      an Amended and Restated Tranche A Note substantially in the form of Exhibit A hereto executed by
Borrower;

(ii)     a Tranche C Note substantially in the form of Exhibit B hereto executed by Borrower;

(iii)    a "Permitted Obligations Designation" executed by Borrower and each Guarantor;

(iv)     a Perfection Certificate executed by Borrower;

(v)      the consent of the Guarantors, substantially the form of Exhibit C hereto executed by the Guarantors; and

(vi)     the consent of the Creditor, substantially the form of Exhibit D hereto executed by the Creditor.

(c)      Additional Closing Documents and Actions.  Lender shall have received the following, in form and

substance satisfactory to it:

(i) evidence that all (A)
authorizations or approvals of any Governmental Authority, and
(B) approvals or consents of any other Person, required in connection with
the execution, delivery and performance of this Amendment shall have been
obtained;

(ii) a certificate of a
senior officer of Borrower, stating that (A) the representations and
warranties contained in Section 5 are true and correct on and as of the
date of such certificate as though made on and as of the Effective Date and
(B) on and as of the Effective Date, after and giving effect to the
amendment of the Credit Agreement contemplated hereby, no Default shall have
occurred and be continuing; and

(iii) a certificate of the
Secretary or Assistant Secretary of Borrower, dated the Effective Date,
certifying (A) copies of the Certificate of Incorporation of Borrower, (B)
copies of the Bylaws of Borrower, (C) copies of the resolutions of the
Board of Directors of Borrower authorizing the execution, delivery and
performance of this Amendment and (D) the incumbency, authority and
signatures of each officer of Borrower authorized to execute and deliver this
Amendment;

(d)      Legal Opinions.  Lender shall have received the opinion of counsel to Loan Parties, dated the Effective

Date, in form and substance satisfactory to Lender.

(e)      Material Adverse Change.  On and as of the Effective Date, there shall have occurred no Material Adverse

Change since the date of this Amendment.

(f)      Representations and Warranties; No Default.  On the Effective Date, after giving effect to the amendment

of the Credit Agreement contemplated hereby:

(i)      the representations and warranties contained in Section 5 shall be true and correct on and as of the
Effective Date as though made on and as of such date; and

(ii)     no Default shall have occurred and be continuing.

(g)      Additional Documents.  Lender shall have received, in form and substance satisfactory to it, such

additional approvals, opinions, documents and other information as Lender may reasonably request.

SECTION 5    
Representations and Warranties. To induce Lender to enter into this
Amendment, Borrower hereby confirms and restates, as of the date hereof, the
representations and warranties made by it in Section 4.1 of the Credit Agreement
and in the other Loan Documents; provided that any representations in
Section 4.1 of the Credit Agreement made as of a certain date only shall be true
and correct as of such date. For the purposes of this Section 5,
(i) each reference in Section 4.1 of the Credit Agreement to this
Agreement, and the words hereof, herein,
hereunder, or words of like import in such Section, shall mean and
be a reference to the Credit Agreement as amended by this Amendment, and
(ii) , clause (i) shall take into account any amendments to any
disclosures made in writing by Borrower and any Guarantor to Lender after the
Closing Date and approved by Lender.

SECTION 6             Release of Claims.

(a)      Release of Claims.  Effective on the First Amendment Effective Date, each of Borrower,

Holdings and any of their respective Subsidiaries and Affiliates (collectively, the "Releasing Parties") hereby
irrevocably releases and forever discharges Lender and Cisco Systems and their successors, assigns, agents,
shareholders, directors, officers, employees, agents, attorneys, parent corporations, subsidiary corporations,
affiliated corporations, affiliates, and each of them (collectively, the "Cisco Released Parties"), from any and
all claims, debts, liabilities, demands, offsets, obligations, costs, expenses, actions and causes of action,
whether sounding in contract or tort or otherwise, of every nature and description, known and unknown, contingent
or non-contingent, which any of the Releasing Parties now has or at any time may hold, by reason of any matter,
cause or thing occurred, done, omitted or suffered to be done (collectively, the "Cisco Released Claims") arising
prior to the date of this Amendment; provided, that the Cisco Released Claims shall not include any claims

against Cisco Systems, Inc. arising under the Cisco Purchase Agreement or any invoices or purchase orders
evidencing the purchase of Cisco Products or services in connection with the use, manufacture or function of any
Cisco Products or services (including, but not limited to, any warranty claims in connection therewith).  For
purposes of this Amendment, a Cisco Released Claim shall be deemed to exist or arise before the date of this
Amendment if it arises from events, facts, conditions, circumstances or the conduct of any Cisco Released Parties
occurring on or before the date of this Amendment (even if the damages caused by such events, facts, conditions,
circumstances or conduct are not suffered until after the date of this Amendment and even if the Cisco Released
Claim does not arise until such damages are suffered).

(b)      Waiver of California Civil Code Section 1542.  Each of Releasing Parties hereby

irrevocably waives the benefits of California Civil Code Section 1542 which provides:  "A general release does
not extend to claims which the creditor does not know or suspect to exist in his favor at the time of executing
the release, which known by him must have materially affected his settlement with the debtor."

(c)      Additional Waivers.  EACH RELEASING PARTY FURTHER AGREES TO ASSUME THE RISK OF ANY AND

ALL UNKNOWN, UNANTICIPATED OR MISUNDERSTOOD DEFENSES, CLAIMS, CAUSES OF ACTION, CONTRACTS, LIABILITIES,
INDEBTEDNESS AND OBLIGATIONS WHICH ARE RELEASED, WAIVED AND DISCHARGED BY THIS AMENDMENT IN FAVOR OF ANY CISCO
RELEASED PARTY, AND HEREBY WAIVES AND RELINQUISHES ALL RIGHTS AND BENEFITS WHICH IT MIGHT OTHERWISE HAVE UNDER
THE AFOREMENTIONED SECTION 1542 OF THE CALIFORNIA CIVIL CODE OR ANY SIMILAR LAW, TO THE EXTENT ANY SUCH LAW MAY
BE APPLICABLE, WITH REGARD TO THE RELEASE OF SUCH UNKNOWN, UNANTICIPATED OR MISUNDERSTOOD DEFENSES, CLAIMS,
CAUSES OF ACTION, CONTRACTS, LIABILITIES, INDEBTEDNESS AND OBLIGATIONS RELEASED HEREUNDER.  TO THE EXTENT (IF
ANY) THAT SUCH LAWS MAY BE APPLICABLE, EACH RELEASING PARTY WAIVES AND RELEASES (TO THE MAXIMUM EXTENT PERMITTED
BY LAW) ANY RIGHT OR DEFENSE WHICH IT MIGHT OTHERWISE HAVE UNDER ANY OTHER LAW OF ANY APPLICABLE JURISDICTION
WHICH MIGHT LIMIT OR RESTRICT THE EFFECTIVENESS OR SCOPE OF ANY OF ITS WAIVERS OR RELEASES UNDER THIS AMENDMENT.

(d)      No Prosecution of Released Claims.  Each of the Releasing Parties agrees that, from

and after the First Amendment Effective Date, it shall not commence or prosecute any action, suit, litigation or
proceeding against any Cisco Released Party to collect or enforce any Cisco Released Claim.

SECTION 7            Miscellaneous.

(a) Credit Agreement
Otherwise Not Affected. Except as expressly amended pursuant hereto, the
Credit Agreement shall remain unchanged and in full force and effect and is
hereby ratified and confirmed in all respects. Lenders execution and
delivery of, or acceptance of, this Amendment and any other documents and
instruments in connection herewith (collectively, the Amendment
Documents) shall not be deemed to create a course of dealing or otherwise
create any express or implied duty by it to provide any other or further
amendments, consents or waivers in the future.

(b) No Reliance.
Borrower hereby acknowledges and confirms to Lender that Borrower is executing
this Amendment and the other Amendment Documents on the basis of its own
investigation and for its own reasons without reliance upon any agreement,
representation, understanding or communication by or on behalf of any other
Person.

(c) Costs and
Expenses. Borrower agrees to pay to Lender on demand the reasonable
out-of-pocket costs and expenses of Lender, and the reasonable fees and
disbursements of counsel to Lender, in connection with the negotiation,
preparation, execution and delivery of this Amendment and any other documents to
be delivered in connection herewith.

(d)      Binding Effect.  This Amendment shall be binding upon, inure to the benefit of and be enforceable by

Borrower, Lender and their respective successors and assigns.

(e)      Governing Law.  This Amendment shall be governed by, and
construed in accordance with, the law of the State of New
York.

(f) Complete Agreement;
Amendments. This Amendment, together with the other Amendment Documents and
the other Loan Documents, contains the entire and exclusive agreement of the
parties hereto and thereto with reference to the matters discussed herein and
therein. This Amendment supersedes all prior commitments, drafts,
communications, discussions and understandings, oral or written, with respect
thereto. This Amendment may not be modified, amended or otherwise altered except
in accordance with the terms of Section 7.1 of the Credit Agreement.

(g) Severability.
Whenever possible, each provision of this Amendment shall be interpreted in such
manner as to be effective and valid under all applicable laws and regulations.
If, however, any provision of this Amendment shall be prohibited by or invalid
under any such law or regulation in any jurisdiction, it shall, as to such
jurisdiction, be deemed modified to conform to the minimum requirements of such
law or regulation, or, if for any reason it is not deemed so modified, it shall
be ineffective and invalid only to the extent of such prohibition or invalidity
without affecting the remaining provisions of this Amendment, or the validity or
effectiveness of such provision in any other jurisdiction.

(h) Counterparts.
This Amendment may be executed in any number of counterparts and by different
parties hereto in separate counterparts, each of which when so executed shall be
deemed to be an original and all of which taken together shall constitute but
one and the same agreement.

(i)      Investigation.  Each of the Releasing Parties acknowledges that it and its counsel

have had an adequate opportunity to make whatever investigation or inquiry they may deem necessary or desirable
in connection with the subject matter of this Amendment prior to the execution hereof and thereof.  Each of the
Releasing Parties acknowledges that (i) it has been represented by independent counsel of its own choice
throughout all of the negotiations which preceded the execution of this Amendment, (ii) it has executed this
Amendment, or any consent, document or agreement related thereto to which it is a party, after seeking the advice
of such independent legal counsel, and (iii) it has executed such agreement, documents or consents voluntarily
and knowingly.

(j)      Interpretation.  This Amendment and the other Amendment Documents are the result of

negotiations between and have been reviewed by counsel to Lender, Borrower and other parties, and are the product
of all parties hereto.  Accordingly, this Amendment and the other Amendment Documents shall not be construed
against Lender merely because of Lender's involvement in the preparation thereof.

(k)      Loan Documents. This Amendment and the other Amendment Documents shall constitute Loan

Documents.

IN WITNESS WHEREOF, the parties hereto have duly executed this Amendment, as of the date first
above written.

Pathnet Telecommunications, Inc., solely in its        
capacity as a "Releasing Party"

By /S/ James M Craig       
                         
Title: Chief Financial Officer

Pathnet Operating, Inc.

By /S/ James M Craig       
                         
Title: Chief Financial Officer

Cisco Systems Capital Corporation

By /S/ James Fukhara       
                         
Title: Chief Credit Officer

Acknowledged:

State Street Bank and Trust Company, as Collateral Agent

By

                                  Title:

---

# EXHIBIT A

# Form of Amended and Restated Tranche A Promissory Note

THIS
NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
ANY OTHER APPLICABLE SECURITIES LAWS. IT MAY NOT BE SOLD OR OTHERWISE
TRANSFERRED UNDER CIRCUMSTANCES THAT WOULD RESULT IN A VIOLATION OF THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT OF 1933 OR SUCH OTHER
LAWS.

U.S.$60,000,000

FOR VALUE RECEIVED, the undersigned, Pathnet Operating, Inc. ("Borrower"), a corporation
organized and existing under the laws of the State of Delaware, HEREBY UNCONDITIONALLY PROMISES TO PAY to the
order of Cisco Systems Capital Corporation ("Lender"), a corporation organized and existing under the laws of the
State of Nevada, the principal sum of SIXTY MILLION United States Dollars (U.S.$60,000,000), or such greater or
lesser amount as represents the aggregate principal amount of the Tranche A loans (the "Loans") made by Lender to
Borrower pursuant to the Credit Agreement referred to below, quarterly in arrears, payable on the dates and in
the amounts indicated in the amortization schedules set forth in the Annex attached hereto (the last such date
being hereinafter referred to as the "Maturity Date").

Borrower further promises to pay interest on the principal amount of each Loan outstanding
hereunder on each Interest Payment Date (as defined below) until the Maturity Date, at a rate per annum equal at
all times during each Interest Period for such Loan to LIBOR for such Interest Period plus "*"
per annum.

The period between the date of a Loan and the Maturity Date shall be divided into successive
periods, each such period being an "Interest Period" for purposes of this Promissory Note.  The initial Interest
Period for a Loan shall begin on the date such Loan is made and end on the next Quarterly Date.  Each subsequent
Interest Period shall begin on the last day of the immediately preceding Interest Period and shall end on the
next succeeding Quarterly Date (with the last Interest Period to end on the Maturity Date).  As used herein,
"LIBOR" means for any Interest Period the rate of interest per annum determined by Lender to be the rate of
interest per annum (rounded upward, if necessary, to the nearest 1/100 of 1%) for deposits in Dollars for three
months appearing on the display page designated as "3750" in the Dow Jones Market Service (formerly known as the
Telerate Service), or any replacement page thereof in the Dow Jones Market Service displaying London interbank
offered rates of major banks for Dollar deposits, at or about 11:00 a.m. (London time) on the second Banking Day
preceding the first day of the applicable calendar quarter in which such Interest Period occurs, provided that if
no, or only one, such offered quotation appears on such display page (or such other replacement page), "LIBOR"
shall be determined by reference to the Reuters Screen LIBO Page of the Reuters Monitor Money Rates Service (or
any replacement page thereof or other applicable Reuters display page) or other comparable source of interest
quotations for such interbank rates selected by Lender; and "Quarterly Date" means the last day of each calendar
quarter.

Interest on each Loan shall be payable in arrears to Lender on the last day of each calendar
quarter and on the Maturity Date (each such date, an "Interest Payment Date"); provided that if any prepayment
hereof is effected other than on an Interest Payment Date, accrued interest hereon shall be due on such
prepayment date as to the principal amount prepaid.

In the event that any amount of principal hereof or interest thereon, or any other amount
payable hereunder or under the Credit Agreement, shall not be paid in full when due (whether at stated maturity,
by acceleration or otherwise), Borrower shall pay interest (after as well as before entry of judgment thereon to
the extent permitted by law) on such unpaid amount to Lender, from the date such amount becomes due until the
date such amount is paid in full, payable on demand of Lender, at a fluctuating rate per annum equal at all times
to the Prime Rate (as defined below) plus "*" per annum (the "Default Rate").  Additionally, and
without limiting the foregoing, following the occurrence and during the continuance of any Event of Default, at
the option of Lender, the interest rate on all Loans outstanding hereunder shall be the Default Rate.

As used herein, "Prime Rate" means for any day the rate of interest in effect for such day as
publicly announced from time to time by Bank of America, N.A., as its prime rate.  Each change in the interest
rate hereon based on a change in the prime rate shall be effective at the opening of business on the day
specified in the public announcement of such change.

All computations of interest hereunder shall be made on the basis of a year of 360 days for the
actual number of days occurring in the period for which any such interest or fee is payable.

Whenever any payment hereunder shall be stated to be due, or whenever any Interest Payment Date
or any other date specified hereunder would otherwise occur, on a day other than a Banking Day, then, except to
the extent otherwise provided hereunder, such payment shall be made, and such Interest Payment Date or other date
shall occur, on the next succeeding Banking Day, and such extension of time shall in such case be included in the
computation of payment of interest hereunder; provided, however, that if such extension would cause such payment

to be made, or such Interest Payment Date or other date to occur, in the next following calendar month, such
payment shall be made and such Interest Payment Date or other date shall occur on the next preceding Banking Day.
As used herein, "Banking Day" means a day other than a Saturday or Sunday on which commercial banks are not
required or authorized by law to close in San Jose, California, except that if the applicable Banking Day relates
to any determination of LIBOR, "Banking Day" means such a day on which dealings are carried out in the applicable
offshore U.S. Dollar interbank market.

Each such payment shall be made on the date when due, in immediately available funds, to
Lender's account at Bank of America, N.A., Concord, California, ABA no. 12100358, to account number 1233124070,
ref. "Pathnet Operating, Inc.," or to such other account of Lender as it from time to time shall designate in a
written notice to Borrower.

All payments of principal, interest and other amounts made on or in respect to this Promissory
Note shall be made in United States Dollars for value received on the date of payment, without setoff,
counterclaim or, to the extent permitted by applicable law, defense, and free and clear of and without deduction
for any present and future Taxes or charges whatsoever.

Lender shall record the date and amount of each Loan made to Borrower, the amount of principal
and interest due and payable from time to time hereunder, each payment thereof, and the resulting unpaid
principal balance hereof, in Lender's internal records, and any such records shall be conclusive evidence absent
manifest error of the amount of the Loans made by Lender and the interest and payments thereon; provided,

however, that Lender's failure so to record shall not limit or otherwise affect the obligations of Borrower
hereunder and under the Credit Agreement to repay the principal of and interest on the Loans.

This Promissory Note replaces and supercedes in its entirety that certain Tranche A Promissory
Note (the "Original Tranche A Note") dated as of September 7, 2000, made by Borrower to the order of Lender in
connection with the Credit Agreement dated as of September 7, 2000 (as amended, modified, renewed or extended
from time to time, the "Credit Agreement") between Borrower and Lender and evidences a continuation and not a
novation or repayment of the Loans evidenced by the Original Tranche A Note.

This Promissory Note is a Note referred to in, and is subject to and entitled to the benefits
of, the Credit Agreement.  Capitalized terms used herein shall have the respective meanings assigned to them in
the Credit Agreement.

The Credit Agreement provides, among other things, for acceleration (which in certain cases
shall be automatic) of the maturity hereof upon the occurrence of certain stated events, in each case without
presentment, demand, protest or further notice of any kind, all of which are hereby expressly waived.

This Promissory Note is subject to prepayment in whole or in part as provided in the Credit
Agreement.

Borrower hereby waives diligence, presentment, protest or notice of total or partial nonpayment
or dishonor with respect to this Promissory Note.

Failure by the holder hereof to exercise any of its rights hereunder in any instance shall not
constitute a waiver thereof in that or any other instance.

Borrower agrees to pay on demand all costs and expenses of Lender and its affiliates, and fees
and disbursements of counsel (excluding allocated costs and expenses for internal legal services), in connection
with the enforcement or attempted enforcement of, and preservation of any rights or interests under, (i) this
Promissory Note, and (ii) any out-of-court workout or other refinancing or restructuring or any bankruptcy or
insolvency case or proceeding, including any losses, costs and expenses sustained by Lender as a result of any
failure by Borrower to perform or observe its obligations contained herein.

This Promissory Note shall be governed by, and construed in accordance with, the law of the
State of New York.

Borrower hereby (a) submits to the non-exclusive jurisdiction of the courts of the State of New
York and the Federal courts of the United States sitting in the Borough of Manhattan (collectively, the "New York
Courts"), for the purpose of any action or proceeding arising out of or relating to this Promissory Note,
(b) irrevocably waives (to the extent permitted by applicable law) any objection which it now or hereafter may
have to the laying of venue of any such action or proceeding brought in any of the New York Courts, and any
objection on the ground that any such action or proceeding in any New York Court has been brought in an
inconvenient forum, and (c) agrees that (to the extent permitted by applicable law) a final judgment in any such
action or proceeding brought in a New York Court shall be conclusive and may be enforced in other jurisdictions
by suit on the judgment or in any other manner permitted by law.

IN WITNESS WHEREOF, Borrower by its duly authorized legal representatives has executed this
Promissory Note on the date and in the year first above mentioned.

Borrower

Pathnet Operating, Inc.

By                             
Title:

---

# Annex to
Tranche A Promissory Note

Amortization

"*"

---

# EXHIBIT B

# Form of Tranche C Promissory Note

THIS
NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
ANY OTHER APPLICABLE SECURITIES LAWS. IT MAY NOT BE SOLD OR OTHERWISE
TRANSFERRED UNDER CIRCUMSTANCES THAT WOULD RESULT IN A VIOLATION OF THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT OF 1933 OR SUCH OTHER
LAWS.

U.S.$25,000,000

FOR VALUE RECEIVED, the undersigned, Pathnet Operating, Inc. ("Borrower"), a corporation
organized and existing under the laws of the State of Delaware, HEREBY UNCONDITIONALLY PROMISES TO PAY to the
order of Cisco Systems Capital Corporation ("Lender"), a corporation organized and existing under the laws of the
State of Nevada, the principal sum of TWENTY FIVE MILLION United States Dollars (U.S.$25,000,000), or such
greater or lesser amount as represents the aggregate principal amount of the Tranche C loans (the "Loans") made
by Lender to Borrower pursuant to the Credit Agreement referred to below, quarterly in arrears, payable on the
dates and in the amounts indicated in the amortization schedules set forth in the Annex attached hereto (the last
such date being hereinafter referred to as the "Maturity Date").

Borrower further promises to pay interest on the principal amount of each Loan outstanding
hereunder on each Interest Payment Date (as defined below) until the Maturity Date, at a rate per annum equal at
all times during each Interest Period for such Loan to LIBOR for such Interest Period plus "*"
per annum.

The period between the date of a Loan and the Maturity Date shall be divided into successive
periods, each such period being an "Interest Period" for purposes of this Promissory Note.  The initial Interest
Period for a Loan shall begin on the date such Loan is made and end on the next Quarterly Date.  Each subsequent
Interest Period shall begin on the last day of the immediately preceding Interest Period and shall end on the
next succeeding Quarterly Date (with the last Interest Period to end on the Maturity Date).  As used herein,
"LIBOR" means for any Interest Period the rate of interest per annum determined by Lender to be the rate of
interest per annum (rounded upward, if necessary, to the nearest 1/100 of 1%) for deposits in Dollars for three
months appearing on the display page designated as "3750" in the Dow Jones Market Service (formerly known as the
Telerate Service), or any replacement page thereof in the Dow Jones Market Service displaying London interbank
offered rates of major banks for Dollar deposits, at or about 11:00 a.m. (London time) on the second Banking Day
preceding the first day of the applicable calendar quarter in which such Interest Period occurs, provided that if
no, or only one, such offered quotation appears on such display page (or such other replacement page), "LIBOR"
shall be determined by reference to the Reuters Screen LIBO Page of the Reuters Monitor Money Rates Service (or
any replacement page thereof or other applicable Reuters display page) or other comparable source of interest
quotations for such interbank rates selected by Lender; and "Quarterly Date" means the last day of each calendar
quarter.

Interest on each Loan shall be payable in arrears to Lender on the last day of each calendar
quarter and on the Maturity Date (each such date, an "Interest Payment Date"); provided that if any prepayment
hereof is effected other than on an Interest Payment Date, accrued interest hereon shall be due on such
prepayment date as to the principal amount prepaid.

In the event that any amount of principal hereof or interest thereon, or any other amount
payable hereunder or under the Credit Agreement, shall not be paid in full when due (whether at stated maturity,
by acceleration or otherwise), Borrower shall pay interest (after as well as before entry of judgment thereon to
the extent permitted by law) on such unpaid amount to Lender, from the date such amount becomes due until the
date such amount is paid in full, payable on demand of Lender, at a fluctuating rate per annum equal at all times
to the Prime Rate (as defined below) plus "*" per annum (the "Default Rate").  Additionally, and
without limiting the foregoing, following the occurrence and during the continuance of any Event of Default, at
the option of Lender, the interest rate on all Loans outstanding hereunder shall be the Default Rate.

As used herein, "Prime Rate" means for any day the rate of interest in effect for such day as
publicly announced from time to time by Bank of America, N.A., as its prime rate.  Each change in the interest
rate hereon based on a change in the prime rate shall be effective at the opening of business on the day
specified in the public announcement of such change.

All computations of interest hereunder shall be made on the basis of a year of 360 days for the
actual number of days occurring in the period for which any such interest or fee is payable.

Whenever any payment hereunder shall be stated to be due, or whenever any Interest Payment Date
or any other date specified hereunder would otherwise occur, on a day other than a Banking Day, then, except to
the extent otherwise provided hereunder, such payment shall be made, and such Interest Payment Date or other date
shall occur, on the next succeeding Banking Day, and such extension of time shall in such case be included in the
computation of payment of interest hereunder; provided,however, that if such extension would cause such payment

to be made, or such Interest Payment Date or other date to occur, in the next following calendar month, such
payment shall be made and such Interest Payment Date or other date shall occur on the next preceding Banking Day.
As used herein, "Banking Day" means a day other than a Saturday or Sunday on which commercial banks are not
required or authorized by law to close in San Jose, California, except that if the applicable Banking Day relates
to any determination of LIBOR, "Banking Day" means such a day on which dealings are carried out in the applicable
offshore U.S. Dollar interbank market.

Each such payment shall be made on the date when due, in immediately available funds, to
Lender's account at Bank of America, N.A., Concord, California, ABA no. 12100358, to account number 1233124070,
ref. "Pathnet Operating, Inc.," or to such other account of Lender as it from time to time shall designate in a
written notice to Borrower.

All payments of principal, interest and other amounts made on or in respect to this Promissory
Note shall be made in United States Dollars for value received on the date of payment, without setoff,
counterclaim or, to the extent permitted by applicable law, defense, and free and clear of and without deduction
for any present and future Taxes or charges whatsoever.

Lender shall record the date and amount of each Loan made to Borrower, the amount of principal
and interest due and payable from time to time hereunder, each payment thereof, and the resulting unpaid
principal balance hereof, in Lender's internal records, and any such records shall be conclusive evidence absent
manifest error of the amount of the Loans made by Lender and the interest and payments thereon; provided,

however, that Lender's failure so to record shall not limit or otherwise affect the obligations of Borrower
hereunder and under the Credit Agreement to repay the principal of and interest on the Loans.

This Promissory Note is a Note referred to in, and is subject to and entitled to the benefits
of, the Agreement dated as of September 7, 2000 (as amended, modified, renewed or extended from time to time, the
"Credit Agreement") between Borrower and Lender.  Capitalized terms used herein shall have the respective
meanings assigned to them in the Credit Agreement.

The Credit Agreement provides, among other things, for acceleration (which in certain cases
shall be automatic) of the maturity hereof upon the occurrence of certain stated events, in each case without
presentment, demand, protest or further notice of any kind, all of which are hereby expressly waived.

This Promissory Note is subject to prepayment in whole or in part as provided in the Credit
Agreement.

Borrower hereby waives diligence, presentment, protest or notice of total or partial nonpayment
or dishonor with respect to this Promissory Note.

Failure by the holder hereof to exercise any of its rights hereunder in any instance shall not
constitute a waiver thereof in that or any other instance.

Borrower agrees to pay on demand all costs and expenses of Lender and its affiliates, and fees
and disbursements of counsel (excluding allocated costs and expenses for internal legal services), in connection
with the enforcement or attempted enforcement of, and preservation of any rights or interests under, (i) this
Promissory Note, and (ii) any out-of-court workout or other refinancing or restructuring or any bankruptcy or
insolvency case or proceeding, including any losses, costs and expenses sustained by Lender as a result of any
failure by Borrower to perform or observe its obligations contained herein.

This Promissory Note shall be governed by, and construed in accordance with, the law of the
State of New York.

Borrower hereby (a) submits to the non-exclusive jurisdiction of the courts of the State of New
York and the Federal courts of the United States sitting in the Borough of Manhattan (collectively, the "New York
Courts"), for the purpose of any action or proceeding arising out of or relating to this Promissory Note,
(b) irrevocably waives (to the extent permitted by applicable law) any objection which it now or hereafter may
have to the laying of venue of any such action or proceeding brought in any of the New York Courts, and any
objection on the ground that any such action or proceeding in any New York Court has been brought in an
inconvenient forum, and (c) agrees that (to the extent permitted by applicable law) a final judgment in any such
action or proceeding brought in a New York Court shall be conclusive and may be enforced in other jurisdictions
by suit on the judgment or in any other manner permitted by law.

IN WITNESS WHEREOF, Borrower by its duly authorized legal representatives has executed this
Promissory Note on the date and in the year first above mentioned.

Borrower

Pathnet Operating, Inc.

By                             
Title:

---

# Annex to
Tranche C Promissory Note

Amortization

"*"

---

# EXHIBIT C

Form of Guarantor Consent



February __, 2001

Cisco Systems Capital Corporation
Worldwide Financial Services
Mailstop SJ-Linc 1/2
170 West Tasman Drive
San Jose, CA  95134-1706

Re:      Pathnet Operating, Inc.

Gentlemen:

The undersigned acknowledges receipt of a copy of the First Amendment Agreement dated February
__, 2001 (the "Amendment") being entered into concurrently herewith by and between you and Pathnet Operating,
Inc. (the "Borrower").

The undersigned, in its capacity as guarantor, acknowledges that its consent to the foregoing
Amendment is not required, but the undersigned nevertheless does hereby consent to the foregoing Amendment and to
the documents and agreements referred to therein and to all future modifications and amendments thereto (subject
to the terms of the Guaranty executed by the undersigned in favor of the State Street Bank and Trust as
Collateral Agent and dated August 9, 2000 (the "Guaranty"), as such Guaranty may be amended from time to time),
and any termination thereof, and to any and all other present and future documents and agreements between or
among the foregoing parties.  Nothing herein shall in any way limit any of the terms or provisions of the
Guaranty of the undersigned or any Collateral Documents related thereto all of which are hereby ratified and
affirmed in all respects.  The undersigned acknowledges that it has read Section 6 and Section 7(i) of the
Amendment and agrees to be bound to the provisions, acknowledgements and representations set forth therein as a
"Releasing Party".

Sincerely yours,

[Guarantor]

By: _____________________________________________             
                                                              Title: ______________________________________________

---

# EXHIBIT D

# Form of Consent of Required Committed Secured Parties

CONSENT (this "Consent") dated as of February __, 2001 is executed by each of the undersigned
in favor of Pathnet Operating, Inc., a Delaware corporation ("Borrower"), Pathnet Telecommunications, Inc., a
Delaware corporation ("Holdings") and Cisco Systems Capital Corporation., a Nevada corporation (the "Cisco").
Capitalized terms used herein but not otherwise defined shall have the meanings set forth in the Intercreditor
Agreement (as defined below).

# RECITALS

WHEREAS, Borrower, Holdings, the Subsidiaries of the Borrower, the Nortel Networks Credit
Facility Lenders and the Nortel Networks Credit Facility Administrative Agent are parties to the Nortel Networks
Credit Agreement; and

WHEREAS, Borrower and Cisco are parties to the Cisco Credit Agreement; and

WHEREAS, Borrower, Holdings, the Subsidiaries of Borrower, the Nortel Networks Credit Facility
Administrative Agent, Cisco and the Collateral Agent are parties to that certain Amended and Restated Collateral
Agency and Intercreditor Agreement (the "Intercreditor Agreement") dated as of September 7, 2000 pursuant to
which the Secured Parties have agreed to share the Collateral as set forth therein; and

WHEREAS, Borrower represents and warrants that there exists no Default or Event of Default
under the Nortel Networks Credit Agreement, the Cisco Credit Agreement or any other Support Document, and that no
Notice of Enforcement in is effect, in each case, on the date of this Consent; and

WHEREAS, Cisco desires to extend to Borrower and Borrower desires to receive from Cisco
additional financing which would qualify as "Permitted Additional Obligations" under the terms of the
Intercreditor Agreement and as "Eligible Secured Debt" under the terms of the Nortel Networks Credit Agreement
pursuant to the form of amendment attached hereto as Exhibit A (the "First Amendment Agreement"); and

WHEREAS, as a condition of the consent of the Required Committed Secured Lenders set forth
herein, Borrower is delivering a Permitted Additional Obligations Designation and is otherwise complying with the
provisions of Section 2.01 of the Intercreditor Agreement for the purposes of confirming that the additional
financing described in the Amendment Agreement would constitute "Permitted Additional Obligations" under the
Intercreditor Agreement even if such additional obligations shall constitute "Cisco Credit Facility Obligations"
under the Intercreditor Agreement after the effective date of this Consent; and

WHEREAS, the parties desire to memorialize the consent of the Required Committed Secured
Parties to the First Amendment Agreement and the amendments set forth therein (the "Amendments");

NOW THEREFOR, the undersigned agree as follows:

1.       Consent: Subject to the limitations set forth in Section 2 hereof, the Required

Committed Secured Parties hereby consent (a) to the execution, delivery and performance of the First Amendment
Agreement by Borrower and Cisco; (b) to each of the Amendments set forth in the First Amendment Agreement and (c)
to the Borrower and/or Cisco (as the case may be) issuing or entering into any promissory notes, documents,
instruments or agreements necessary or desirable to execute and consummate the intent of the First Amendment
Agreement and the Amendments set forth therein.  The Required Committed Secured Parties further agree that after
the effectiveness of the First Amendment Agreement (A) the definition of "Cisco Credit Agreement" in the
Intercreditor Agreement shall mean the Cisco Credit Agreement as amended by the First Amendment Agreement, (B)
the definition of "Cisco Credit Facility Obligations shall include, without limitation, the additional financing
described in the Amendment Agreement, and (C) the definition of "Obligations" in the Intercreditor Agreement
shall include all of the obligations of Borrower (including, without limitation, all principal, interest and fees
due under the "Loans" (as defined the Cisco Credit Agreement)) to Lender under the Cisco Credit Agreement as
amended by the First Amendment Agreement.

2.       Reservation of Rights.  Other than as expressly set forth in this Consent, the Nortel

Networks Credit Agreement, the Cisco Credit Agreement, the Intercreditor Agreement and any other Support
Documents and Security Documents remain in full force effect and are fully enforceable in accordance with their
terms. This Consent creates no course of dealing that would require the Required Committed Secured Parties to
grant similar waivers or consents to Cisco or Borrower in the future.

3.       Counterparts.  This consent may be executed in any number of counterparts and by

different parties hereto in separate counterparts, each of which when so executed shall be deemed an original and
all of which taken together shall constitute but one in the same agreement.

IN WITNESS WHEREOF, this Consent is executed as of the first date written above.

Required Committed Secured Parties:

NORTEL NETWORKS, INC. as Nortel Networks                              
Credit Facility Administrative Agent

By                             
Title:

CISCO SYSTEMS CAPITAL CORPORATION, as a Secured Party

By                             
Title:

Acknowledged and Agreed:

PATHNET OPERATING, INC., a Delaware
corporation

By:_______________________
          Name:
          Title:

PATHNET TELECOMMUNICATIONS, INC., a
Delaware corporation

By:_______________________

PATHNET FIBER EQUIPMENT, LLC., a Delaware
limited liability company

By:_______________________

PATHNET REAL ESTATE, LLC., a Delaware
limited liability company

By:_______________________
          Name:
          Title: