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                                                                   EXHIBIT 10.30

                                FOURTH AMENDMENT
                                       TO
                                CREDIT AGREEMENT


         THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (this "Fourth Amendment") is
dated as of the 1st day of July, 1998 and entered into among METRO NETWORKS,
INC., a Delaware corporation (the "Borrower"), the Lenders party thereto, and
NATIONSBANK, N.A. (successor through merger to NationsBank of Texas, N.A.), a
national banking association, individually and as Administrative Lender (in such
latter capacity, the "Administrative Lender").

                                   WITNESSETH:

         WHEREAS, the Borrower, the Lenders, and the Administrative Lender
entered into a Credit Agreement, dated as of October 22, 1996, for a loan
facility in the amount of $30,000,000 (as amended, restated, waived or otherwise
modified from time to time, including without limitation, the First Amendment
dated September 30, 1997, between the Borrower, the Lenders party thereto, and
the Administrative Lender, the Second Amendment dated December 31, 1997 between
the Borrower, the Lenders party thereto and the Administrative Lender, and the
Third Amendment dated January 1, 1998 between the Borrower, the Lenders party
thereto and the Administrative Lender, the "Credit Agreement"); and

         WHEREAS, the Lenders, the Administrative Lender, and the Borrower have
agreed to amend the Credit Agreement to make certain changes to the terms
therein upon the terms and conditions set forth below;

         NOW, THEREFORE, for valuable consideration hereby acknowledged, the
Borrower, the Lenders and the Administrative Lender agree as follows:

         SECTION 1.   Definitions.

                  (a) Definitions, Generally. Unless specifically defined or
         redefined below, capitalized terms used herein shall have the meanings
         ascribed thereto in the Credit Agreement.

                  (b) Definition of Intercompany Notes. The definition of
         "Intercompany Notes" in Article 1 on page 8 of the Credit Agreement is
         hereby deleted in its entirety and the following definition of
         "Intercompany Notes" shall be substituted in its stead:

                           "Intercompany Notes" shall mean (a) any promissory
                  note executed by any Subsidiary made payable to the order of
                  the Borrower in the original principal amount not to exceed
                  $30,000,000 evidencing loans and advances made or to be made
                  by the Borrower to such Subsidiary, together with any
                  extension, renewal, increase or amendment thereof, or 
                  substitution therefor


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                  and (b) any promissory note or series of promissory notes
                  executed by a Subsidiary of the Borrower and made payable to
                  the order of the Borrower, in the aggregate original
                  principal amount for all such notes not to exceed
                  $100,000,000, evidencing loans and advances made by the
                  Borrower to such Subsidiaries, together with any extension,
                  renewal, increase or amendment thereof, or substitution
                  therefor.

                  (c)      Definition of Year 2000 Compliant. The definition of

                  "Year 2000 Compliant" shall be added to the end of Article 1
                  in alphabetical order as follows:

                           "Year 2000 Compliant" shall have the meaning ascribed
                  thereto in Section 4.1(y) hereof.

         SECTION 2.        Addition of Section 4.1(y) of the Credit Agreement. 
Section 4.1(y) shall be added to Article 4 on page 44 of the Credit Agreement to
read as follows:

                           (y) Year 2000 Compliance. The Borrower has (i)
                  undertaken a detailed review and assessment of all areas
                  within its business and operations that could be adversely
                  affected by the "Year 2000 Problem" (that is, the risk that
                  computer applications used by the Borrower may be unable to
                  recognize and perform property date-sensitive functions
                  involving certain dates prior to and any date after December
                  31, 1999), (ii) developed a detailed plan and timeline for
                  addressing the Year 2000 Problem on a timely basis, and (iii)
                  to date, implemented that plan in accordance with that
                  timetable. The Borrower reasonably anticipates that all
                  computer applications that are material to its business and
                  operations will on a timely basis be able to perform properly
                  date-sensitive functions for all dates before and after
                  January 1, 2000 (that is, be "Year 2000 Compliant").

         SECTION 3.        Addition of Section 5.16 of the Credit Agreement. 
Section 5.16 shall be added to Article 5 on page 48 of the Credit Agreement to
read as follows:

                           5.16 Year 2000 Compliance. The Borrower will promptly
                  notify the Administrative Lender in the event the Borrower
                  discovers or determines that any computer application
                  (including those of its suppliers and vendors) that is
                  material to its or any of its Subsidiaries' business and
                  operations will not be Year 2000 Compliant on a timely basis,
                  except to the extent that such failure could not be reasonably
                  expected to have a Material Adverse Effect.

         SECTION 4.        Addition of Section 5.17 of the Credit Agreement. 
Section 5.17 shall be added to Article 5 on page 48 of the Credit Agreement to
read as follows:

                           5.17 Formation and Capitalization of Metro Networks
                  Services, Inc. and Metro Networks Communications, Limited
                  Partnership. Prior to such time as the Borrower or any
                  Subsidiary


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                  of the Borrower makes any equity contribution (in cash or
                  any other tangible or intangible asset) or any loan or other
                  advance to either Metro Networks Services, Inc. or Metro
                  Networks Communications, Limited Partnership, the Borrower
                  agrees that the Administrative Lender shall have received
                  (a) a pledge of 100% of the capital stock and partnership
                  interests, respectively, of Metro Networks Services, Inc.
                  and Metro Networks Communications, Limited Partnership in
                  form and substance satisfactory to the Administrative
                  Lender, (b) a guaranty of the Obligations by Metro Networks
                  Services, Inc. and Metro Networks Communications, Limited
                  Partnership, (c) a security agreement and other security
                  documents granting a Lien on 100% of the intangible and
                  tangible assets of Metro Networks Services, Inc. and Metro
                  Networks Communications, Limited Partnership, (d) a pledge
                  of each Intercompany Note to secure the Obligations, each
                  such pledge in form and substance acceptable to the
                  Administrative Agent, and (e) an opinion of counsel
                  acceptable to the Administrative Lender regarding the due
                  organization and formation of such entities and the
                  authorization of such entities to execute their respective
                  Loan Documents.

         SECTION 4.        Amendment to Section 7.3(g) of the Credit Agreement.
Section 7.3(g) in Article 7 on page 55 of the Credit Agreement shall be deleted
in its entirety and the following Section 7.3(g) shall be substituted in its
stead:

                           (g)   Investments in Subsidiaries permitted pursuant
                  to Section 7.8 hereof and pursuant to the Intercompany Notes 
                  (without duplication); and

         SECTION 5.        Amendment to Section 7.5(c) of the Credit Agreement.
Section 7.5(c) in Article 7 on page 56 of the Credit Agreement shall be deleted
in its entirety and the following Section 7.5(c) shall be substituted in its
stead:

                           (c)   create or acquire any Subsidiary, except the
                  Borrower may create (i) Subsidiaries as permitted by Section
                  7.6 hereof, (ii) Metro Networks Services, Inc., a Delaware
                  corporation and wholly owned Subsidiary of Metro Networks
                  Communications, Inc., and (iii) Metro Networks Communications,
                  Limited Partnership, a Delaware limited partnership and wholly
                  owned Subsidiary of Metro Networks Communications, Inc. and
                  Metro Networks Services, Inc.

         SECTION 6.        Amendment to Section 8.1. Section 8.1 in Article 8 of
the Credit Agreement is amended by deleting the "or" before subparagraph (o),
deleting the period at the end of subparagraph (o) and substituting ", or"
instead, and adding the following subparagraph (p):

                  (p)      The Borrower shall fail to be Year 2000 Compliant.

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         SECTION 7.        Affirmation. The Borrower hereby acknowledges and 
agrees that nothing in this Fourth Amendment shall affect the Borrower's
obligations under the Credit Agreement or the other Loan Documents executed in
connection therewith (except as specifically provided in this Fourth Amendment),
which remain valid, binding and enforceable, and except as amended hereby,
unamended, or shall constitute a waiver by the Lenders of any of their rights or
remedies, now or at any time in the future, with respect to any requirement
under the Credit Agreement or the other Loan Documents or with respect to an
Event of Default or Default, occurring now or at any time in the future.

         SECTION 8.        Conditions Precedent. This Fourth Amendment shall 
not be effective until:

                  (a)      all proceedings of the Borrower taken in connection 
         with this Fourth Amendment and the transactions contemplated hereby
         (including, without limitation, the formation of Metro Network
         Services, Inc. and Metro Networks Communications, Limited Partnership)
         shall be satisfactory in form and substance to the Administrative
         Lender and Lenders signatory hereto, and

                  (b)      the Administrative Lender and Lenders shall have each
         received such documents, instruments, and certificates, etc., each in
         form and substance satisfactory to the Lenders, as the Lenders shall
         deem necessary or appropriate in connection with this Fourth Amendment
         and the transactions contemplated hereby.

         SECTION 9.        Representations and Warranties. The Borrower 
represents and warrants to the Lenders and the Administrative Lender that (a)
the Borrower has the corporate power and has taken all necessary corporate
action, to authorize it to enter into and deliver this Fourth Amendment and all
related documentation, (b) this Fourth Amendment constitutes its legal, valid,
and binding obligations, enforceable in accordance with the terms hereof
(subject as to enforcement of remedies to any applicable bankruptcy,
reorganization, moratorium, or other laws or principles of equity affecting the
enforcement of creditors' rights generally), (c) there exists no Event of
Default or Default under the Credit Agreement after giving effect to this Fourth
Amendment, (d) its representations and warranties set forth in the Credit
Agreement and other Loan Documents are true and correct on the date hereof after
giving effect to this Fourth Amendment, (e) it has complied with all agreements
and conditions to be complied with by it under the Credit Agreement and the
other Loan Documents by the date hereof, (f) the Credit Agreement, as amended
hereby, and the other Loan Documents remain in full force and effect, and (g) no
notice to, or consent of, any Person is required under the terms of any
agreement of the Borrower in connection with the execution of this Fourth
Amendment and the transactions contemplated hereby, except such notices that
have been given or consents that have been obtained.

         SECTION 10.       Further Assurances. The Borrower shall execute and 
deliver such further agreements, documents, instruments, and certificates in
form and substance satisfactory to the Administrative Lender, as the
Administrative Lender or any Lender may deem reasonably necessary or appropriate
in connection with this Fourth Amendment.

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         SECTION 11.       Counterparts. This Fourth Amendment and the other 
Loan Documents may be executed in any number of counterparts, all of which taken
together shall constitute one and the same instrument. In making proof of any
such agreement, it shall not be necessary to produce or account for any
counterpart other than one signed by the party against which enforcement is
sought.

         SECTION 12.       GOVERNING LAW. THIS AGREEMENT AND THE OTHER LOAN 
DOCUMENTS SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE
STATE OF TEXAS; PROVIDED, HOWEVER, THAT PURSUANT TO ARTICLE 5069-15.10(B), TITLE
79, REVISED CIVIL STATUTES OF TEXAS, 1925, AS AMENDED, IT IS AGREED THAT THE
PROVISIONS OF CHAPTER 15, TITLE 79, REVISED CIVIL STATUTES OF TEXAS, 1925, AS
AMENDED, SHALL NOT APPLY TO THE ADVANCES, THIS AGREEMENT AND THE OTHER LOAN
DOCUMENTS. WITHOUT EXCLUDING ANY OTHER JURISDICTION, THE BORROWER AGREES THAT
THE STATE AND FEDERAL COURTS OF TEXAS LOCATED IN DALLAS, TEXAS SHALL HAVE
JURISDICTION OVER PROCEEDINGS IN CONNECTION WITH THIS FOURTH AMENDMENT AND THE
OTHER LOAN DOCUMENTS.

         SECTION 13.       WAIVER OF JURY TRIAL. EACH OF THE BORROWER, THE
ADMINISTRATIVE LENDER AND THE LENDERS HEREBY KNOWINGLY VOLUNTARILY, IRREVOCABLY
AND INTENTIONALLY WAIVE, TO THE MAXIMUM EXTENT PERMITTED BY LAW, ALL RIGHT TO
TRIAL BY JURY IN ANY ACTION, PROCEEDING OR CLAIM ARISING OUT OF OR RELATED TO
ANY OF THE LOAN DOCUMENTS OR THE TRANSACTIONS CONTEMPLATED THEREBY. THIS
PROVISION IS A MATERIAL INDUCEMENT TO EACH LENDER ENTERING INTO THIS FOURTH
AMENDMENT AND MAKING ANY ADVANCES HEREUNDER.

         SECTION 14.       ENTIRE AGREEMENT. THIS FOURTH AMENDMENT TOGETHER 
WITH THE OTHER LOAN DOCUMENTS, REPRESENTS THE FINAL AGREEMENT BETWEEN THE
PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR
SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES HERETO. THERE ARE NO UNWRITTEN ORAL
AGREEMENTS BETWEEN THE PARTIES.


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         IN WITNESS WHEREOF, this Fourth Amendment to Credit Agreement is
executed as of the date first set forth above.


BORROWER:                                   METRO NETWORKS, INC.


                                            /s/ TIMOTHY D. MCMILLIN
                                            -----------------------------------
                                            By:      Timothy D. McMillin
                                            Its:     Senior Vice President


ADMINISTRATIVE LENDER:                      NATIONSBANK, N.A.,
                                            as Administrative Lender

                                            /s/ WHITNEY L. BUSSE
                                            -----------------------------------
                                            By:      Whitney L. Busse
                                            Its:     Vice President



LENDERS:                                    NATIONSBANK, N.A., as a Lender


                                            /s/ WHITNEY L. BUSSE
                                            -----------------------------------
                                            By:      Whitney L. Busse
                                            Its:     Vice President



                                            THE BANK OF NOVA SCOTIA, as a Lender


                                            /s/ BRIAN ALLEN
                                            -----------------------------------
                                            By: Brian Allen
                                               --------------------------------
                                            Its:
                                                -------------------------------

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