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                                                                   EXHIBIT 10.27
                                                                [Execution copy]

                       AMENDMENT NO. 1 TO CREDIT AGREEMENT
                        AND GUARANTY AND PLEDGE AGREEMENT

               AMENDMENT NO. 1 TO CREDIT AGREEMENT AND GUARANTY AND PLEDGE
AGREEMENT dated as of April 10, 2000 in respect of (i) the Credit Agreement
dated as of August 13, 1999 (the "Credit Agreement") between Lamar Media Corp.
(the "Borrower"), the Subsidiary Guarantors party thereto, the lenders party
thereto, and The Chase Manhattan Bank, as Administrative Agent (in such
capacity, the "Administrative Agent"), and (ii) the Guaranty and Pledge
Agreement dated as of September 15, 1999 (the "Holdings Guaranty and Pledge
Agreement") between Lamar Advertising Company ("Holdings") and the
Administrative Agent.

               The Borrower and Holdings have requested that the Administrative
Agent consent to certain amendments to the Credit Agreement and the Holdings
Guaranty and Pledge Agreement. The Administrative Agent, pursuant to authority
granted by, and having obtained all necessary consents of, the Required Lenders
(as defined in the Credit Agreement), has agreed to such amendments and,
accordingly, the parties hereto hereby agree as follows:

               Section 1. Definitions. Terms defined in the Credit Agreement and
used herein are used herein as defined therein.

               Section 2. Amendment. Subject to the execution and delivery
hereof by the Borrower, Holdings, the Subsidiary Guarantors and the
Administrative Agent, but effective as of the date hereof, the Credit Agreement,
and the Holdings Guaranty and Pledge Agreement shall be amended as follows:

               2.01. General. References in the Credit Agreement and the
Holdings Guaranty and Pledge Agreement, respectively (including references to
the Credit Agreement and the Holdings Guaranty and Pledge Agreement as amended
hereby) to "this Agreement" (and indirect references such as "hereunder",
"hereby", "herein" and "hereof") shall be deemed to be references to the Credit
Agreement and the Holdings Guaranty and Pledge Agreement, respectively, as
amended hereby.

               2.02. Amendment to Credit Agreement. Clause (v) of Section
7.05(a) of the Credit Agreement is hereby amended in its entirety to read as
follows:

               "(v) Investments consisting of (x) loans made by the Borrower
         to any Special Acquisition Subsidiary (as defined in the Holdings
         Guaranty and Pledge Agreement), so long as (A) such loan is made to
         such Special Acquisition Subsidiary to enable the repayment of
         Indebtedness assumed in connection with the acquisition referred to in
         clause (b) of Article V of the Holdings Guaranty and Pledge Agreement,
         (B) no such loan shall be outstanding for a period of more than five
         Business Days unless, prior to the exploration of such period, such
         Special Acquisition Subsidiary shall have been contributed to the
         Borrower and become a Wholly Owned Subsidiary of the Borrower and (C)
         the aggregate principal amount of all such loans outstanding at any one
         time to



                                 Amendment No. 1


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         all Special Acquisition Subsidiaries shall not exceed $100,000,000 and
         (y) other Investments in Affiliates not exceeding $15,000,000 at any
         one time outstanding."

               2.03. Amendment to Holdings Guaranty and Pledge Agreement.
Clauses (b) and (e) of Article V of the Holdings Guaranty and Pledge Agreement
shall be amended in their entirety to read as follows:

               "(b) acquire any property, other than Investments in equity
         securities in the Borrower and cash and cash equivalents, and other
         than Investments in Special Acquisition Subsidiaries and, for purposes
         hereof, "Special Acquisition Subsidiaries" shall mean any entity formed
         by Holdings that is a Wholly Owned Subsidiary of Holdings but not a
         Subsidiary of the Borrower, and that is formed for the sole purpose of
         affecting a tax free acquisition of another corporation (the "Target")
         under Section 368(a)(1)(A) and 368(a)(2)(E) of the Code, in which
         Holdings invests not more than $1,000 in cash at any one time and which
         Wholly Owned Subsidiary is contributed to the Borrower (and, thereby
         becomes a Wholly Owned Subsidiary of the Borrower) within five Business
         Days after the consummation of the merger or other transactions
         resulting in the acquisition of the Target;

               (c) engage in any business or other activity other than the
         business of holding the shares of capital stock of the Borrower and
         (subject to the conditions set forth in clause (b) above, Special
         Acquisition Subsidiaries) and activities relating to Qualified Holdings
         Obligations, or"

               Section 3. Miscellaneous. Except as expressly herein provided,
the Credit Agreement and the Holdings Guaranty and Pledge Agreement shall remain
unchanged and in full force and affect. This Amendment No. 1 may be executed in
any number of counterparts, all of which taken together shall constitute one and
the same amendatory instrument and any of the parties hereto may execute this
Amendment No. 1 by signing any such counterpart. This Amendment No. 1 shall be
governed by, and construed in accordance with, the law of the State of New York.

               IN WITNESS WHEREOF, the parties hereto have caused this amendment
No. 1 to be duly executed as of the day and year first above written.


                              BORROWER AND HOLDINGS


LAMAR MEDIA CORP.                     LAMAR ADVERTISING COMPANY



By     /s/ Keith A. Istre             By   /s/ Keith A. Istre
  -----------------------------         -----------------------------------
  Title:                                Title:



                                 Amendment No. 1