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                                                                    EXHIBIT 10.1


                                JOINDER AGREEMENT

         JOINDER AGREEMENT dated as of June 1, 2000, by the undersigned, (the
"Additional Subsidiary Guarantor"), in favor of The Chase Manhattan Bank, as
administrative agent for the Lenders party to the Credit Agreement referred to
below (in such capacity, together with its successors in such capacity, the
"Administrative Agent").

         Lamar Media Corp. (formerly Lamar Advertising Company), a Delaware
corporation (the "Borrower"), and certain of its subsidiaries (collectively, the
"Existing Subsidiary Guarantors" and, together with the Borrower, the "Securing
Parties") are parties to a Credit Agreement dated August 13, 1999 (as modified
and supplemented and in effect from time to time, the "Credit Agreement",
providing, subject to the terms and conditions thereof, for extensions of credit
(by means of loans and letters of credit) to be made by the lenders therein
(collectively, together with any entity that becomes a "Lender" party to the
Credit Agreement after the date hereof as provided therein, the "Lenders" and,
together with Administrative Agent and any successors or assigns of any of the
foregoing, the "Secured Parties") to the Borrower in an aggregate principal or
face amount not exceeding $1,000,000,000 (which, in the circumstances
contemplated by Section 2.01(d) thereof, may be increased to $1,400,000,000). In
addition, the Borrower may from time to time be obligated to one or more of the
Lenders under the Credit Agreement in respect of Hedging Agreements under and as
defined in the Credit Agreement (collectively, the "Hedging Agreements").

         In connection with the Credit Agreement, the Borrower, the Existing
Subsidiary Guarantors and the Administrative Agent are parties to the Pledge
Agreement dated September 15, 1999 (the "Pledge Agreement") pursuant to which
the Securing Parties have, inter alia, granted a security interest in the
Collateral (as defined in the Pledge Agreement) as collateral security for the
Secured Obligations (as so defined). Terms defined in the Pledge Agreement are
used herein as defined therein.

         To induce the Secured Parties to enter into the Credit Agreement, and
to extend credit thereunder and to extend credit to the Borrower under Hedging
Agreements, and for other good and valuable consideration the receipt and
sufficiency of which are hereby acknowledged, the Additional Subsidiary
Guarantor has agreed to become a party to the Credit Agreement and the Pledge
Agreement as a "Subsidiary Guarantor" thereunder, and to pledge and grant a
security interest in the Collateral (as defined in the Pledge Agreement).

         Accordingly, the parties hereto agree as follows:

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

         Section 2. Joinder to Agreements. Effective upon the execution and
delivery hereof, the Additional Subsidiary Guarantor hereby agrees that it shall
become "Subsidiary Guarantor" under and for all purposes of the Credit Agreement
and the Pledge Agreement with all the rights and


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obligations of a Subsidiary Guarantor thereunder. Without limiting the
generality of the foregoing, the Additional Subsidiary Guarantor hereby:

                  (i) jointly and severally with the other Subsidiary Guarantors
         party to the Credit Agreement guarantees to each Secured Party and
         their respective successors and assigns the prompt payment in full when
         due (whether at stated maturity, by acceleration or otherwise) of all
         Guaranteed Obligations in the same manner and to the same extent as is
         provided in Article III of the Credit Agreement;

                  (ii) pledges and grants the security interests in all right,
         title and interest of the Additional Subsidiary Guarantor in all
         Collateral (as defined in the Pledge Agreement) now owned or hereafter
         acquired by the Additional Subsidiary Guarantor and whether now
         existing or hereafter coming into existence provided for by Article III
         of the Pledge Agreement as collateral security for the Secured
         Obligations and agrees that Annex 1 thereof shall be supplemented as
         provided in Appendix A hereto;

                  (iii) makes the representations and warranties set forth in
         Article IV of the Credit Agreement and in Article II of the Pledge
         Agreement, to the extent relating to the Additional Subsidiary
         Guarantor or to the Pledged Equity evidenced by the certificates, if
         any, identified in Appendix A hereto; and

                  (iv) submits to the jurisdiction of the courts, and waives
         jury trial, as provided in Sections 10.09 and 10.10 of the Credit
         Agreement.

         The Additional Subsidiary Guarantor hereby instructs its counsel to
deliver the opinions referred to in Section 6.10(a)(iii) of the Credit Agreement
to the Secured Parties.


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         IN WITNESS WHEREOF, the Additional Subsidiary Guarantor has caused this
Joinder Agreement to be duly executed and delivered as of the day and year first
above written.

                                     Outdoor West, Inc. of Georgia,
                                     a Georgia corporation



                                     By:   /s/ Keith A. Istre
                                           ---------------------------------
                                           Keith A. Istre
                                           Vice President - Finance and
                                           Chief Financial Officer

                                     Outdoor West, Inc. of Tennessee,
                                     a Georgia corporation



                                     By:   /s/ Keith A. Istre
                                           ---------------------------------
                                           Keith A. Istre
                                           Vice President - Finance and
                                           Chief Financial Officer



Attested:



By:  /s/ James R. McIlwain
     ----------------------------------
     James R. McIlwain, Secretary

Accepted and agreed:

THE CHASE MANHATTAN BANK,
as Administrative Agent



By:    /s/ William E. Rottino
   ------------------------------------
Title: Vice President


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The undersigned hereby respectively pledges and grants a security interest in
the Pledged Equity and evidenced by the certificate listed in Appendix A hereto
and agrees that Annex 1 of the above-referenced Pledge Agreement is hereby
supplemented by adding thereto the information listed on Appendix A.

Lamar Advertising of Macon, LLC, Issuee of Stock


By:      The Lamar Company, L.L.C.
         Its sole and managing member


By:    /s/ Keith A. Istre
       ------------------------------------
       Keith A. Istre
Title: Vice President-Finance


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SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT



PLEDGOR OWNERSHIP                            ISSUER                    NO. SHARES      CERT. NO.     %
- -----------------                            ------                    ----------      ---------     -
                                                                                         
Lamar Advertising of Macon, LLC              Outdoor West, Inc. of     1,000           5             100
                                             Georgia




PLEDGOR OWNERSHIP                            ISSUER                    NO. SHARES      CERT. NO.     %
- -----------------                            ------                    ----------      ---------     -
                                                                                        
Lamar Advertising of Macon, LLC              Outdoor West, Inc. of     1,000           2             100
                                             Tennessee



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                  SCHEDULE OF ADDITIONAL SUBSIDIARY GUARANTORS



GUARANTOR*                                                   DATE OF JOINDER AGREEMENT
- ----------                                                   -------------------------
                                                          
Lamar Advertising of Texas, Inc.                             June 19, 2000

Lamar Advantage GP Company                                   June 19, 2000

Lamar Advantage Holding Company                              June 19, 2000

Lamar Advantage LP Company, L.L.C.                           June 19, 2000

Lamar Advantage Outdoor Company, L.P.                        June 19, 2000

Lamar Ember, Inc.                                            July 8, 2000

Lamar Advertising of Macon, L.L.C.                           May 16, 2000

Lamar T.T.R., L.L.C.                                         June 1, 2000

Mississippi Logos, L.L.C.                                    May 5, 2000

Oklahoma Logos, L.L.C.                                       May 5, 2000

New Jersey Logos, L.L.C.                                     May 3, 2000

Georgia Logos, L.L.C.                                        May 5, 2000




*The supplements to Annex 1/Appendix A to the Joinder Agreements of each
additional guarantor are set forth below in their entirety.


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        SUPPLEMENT TO LAMAR ADVERTISING OF TEXAS, INC. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT




PLEDGOR OWNERSHIP                       ISSUER                         NO. SHARES      CERT. NO.     %
- -----------------                       ------                         ----------      ---------     -
                                                                                        
Lamar Media Corp.                       Lamar Advertising of Texas,    100             4             100
                                        Inc.



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         SUPPLEMENT TO LAMAR ADVANTAGE GP COMPANY, LLC JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT



PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                        
Lamar Advertising of Texas, Inc.     Lamar Advantage GP Company, LLC   1,000           1             100



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        SUPPLEMENT TO LAMAR ADVANTAGE HOLDING COMPANY JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT





PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
Lamar Advantage Outdoor Company,     Lamar Advantage Holding Company   100             2             100
L.P.



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       SUPPLEMENT TO LAMAR ADVANTAGE LP COMPANY, L.L.C. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT




PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                        
Lamar Advertising of Texas, Inc.     Lamar Advantage LP Company, LLC   1,000           1             100



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      SUPPLEMENT TO LAMAR ADVANTAGE OUTDOOR COMPANY, L.P. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT





PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
Lamar Advantage GP Company, LLC      Lamar Advantage Outdoor Company,  N/A             1GP           0.1
                                     L.P.

Lamar Advantage LP Company, LLC      Lamar Advantage Outdoor           N/A             1LP           99.9
                                     Company, L.P.



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                SUPPLEMENT TO LAMAR EMBER, INC. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT



PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                        
The Lamar Company, L.L.C.            Lamar Ember, Inc.                 1,000           2             100



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       SUPPLEMENT TO LAMAR ADVERTISING OF MACON, L.L.C. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT



PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
The Lamar Company, L.L.C.            Lamar Advertising of Macon,       100             2             100
                                     L.L.C.



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              SUPPLEMENT TO LAMAR T.T.R., L.L.C. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT




PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
Lamar Advertising of Youngstown,     Lamar T.T.R., L.L.C.              1,000           1             100
Inc.



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            SUPPLEMENT TO MISSISSIPPI LOGOS, L.L.C. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT





PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                        
Interstate Logos, Inc.               Mississippi Logos L.L.C.          1,000           1             100



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             SUPPLEMENT TO OKLAHOMA LOGOS, L.L.C. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT




PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
Interstate Logos, Inc.               Oklahoma Logos, L.L.C.            1,000           1             100



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            SUPPLEMENT TO NEW JERSEY LOGOS, L.L.C. JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT




PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
Interstate Logos, Inc.               New Jersey Logos, L.L.C.          1,000           1             100



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               SUPPLEMENT TO GEORGIA LOGOS, LLC JOINDER AGREEMENT

SUPPLEMENT TO ANNEX 1

                                                 APPENDIX A TO JOINDER AGREEMENT




PLEDGOR OWNERSHIP                    ISSUER                            NO. SHARES      CERT. NO.     %
- -----------------                    ------                            ----------      ---------     -
                                                                                         
Interstate Logos, Inc.               Georgia Logos, LLC                1,000           1             100



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