Document:

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                                                                     EXHIBIT 4.1

                             SUPPLEMENTAL INDENTURE

                                       OF

                                   GUARANTORS

     THIS SUPPLEMENTAL INDENTURE dated as of August 8, 2000 is delivered
pursuant to Section 10.04 of the Indenture dated as of November 15, 1996 (as
heretofore or hereafter modified and supplemented and in effect from time to
time, the "Indenture") among LAMAR MEDIA CORP., a Delaware corporation,
(formerly Lamar Advertising Company) certain of its subsidiaries ("Guarantors")
and STATE STREET BANK AND TRUST COMPANY, a Massachusetts banking corporation, as
Trustee ("Trustee") (all terms used herein without definition having the
meanings ascribed to them in the Indenture).

     The undersigned hereby agree that:

     1. The undersigned is a Guarantor under the Indenture with all of the
rights and obligations of a Guarantor thereunder.

     2. The undersigned hereby grants, ratifies and confirms the guarantee
provided for by Article Ten of the Indenture to guarantee unconditionally,
jointly and severally with the other Guarantors, to each Holder of a Note
authenticated and delivered by the Trustee, and to the Trustee on behalf of such
Holder, the due and punctual payment of the principal of (and premium, if any)
and interest on such Note when and as the same shall become due and payable.

     3. The undersigned hereby represents and warrants that the representations
and warranties set forth in the Indenture, to the extent relating to the
undersigned as Guarantor, are correct on and as of the date hereof.

     4. All notices, requests and other communications provided for in the
Indenture should be delivered to the undersigned at the address specified in
Section 12.02 of the Indenture.

     5. A counterpart of this Supplemental Indenture may be attached to any
counterpart of the Indenture.

     6. This Supplemental Indenture shall be governed by and construed in
accordance with the laws of the State of New York.

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     IN WITNESS WHEREOF, the undersigned have caused this Supplemental Indenture
to be duly executed as of the day and year first above written.

                                       Guarantor:

                                       Lamar Ohio Outdoor Holding Corp.
                                       an Ohio 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:

STATE STREET BANK AND TRUST
      COMPANY, as Trustee

By: /s/ Jason G. Gregory
    ----------------------------
Title: Assistant Vice President
       -------------------------

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                        Additional Subsidiary Guarantors

Lamar Kyo, Inc.

Lamar Oklahoma Holding Company, Inc.

Lamar I-40 West, Inc.

Lamar Benches, Inc.

Lamar Advertising of Oklahoma, Inc.

LC Billboard, L.L.C.

Lamar Wright Poster Corp.

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                                                                     EXHIBIT 4.2

                             SUPPLEMENTAL INDENTURE

                       TO INDENTURE DATED AUGUST 15, 1997

     THIS SUPPLEMENTAL INDENTURE dated as of August 8, 2000, is delivered
pursuant to Section 4.11 of the Indenture dated as of August 15, 1997 (as
heretofore or hereafter modified and supplemented and in effect from time to
time, the "1997 Indenture") among OUTDOOR COMMUNICATIONS, INC., a Delaware
corporation, certain of its subsidiaries (the "Guarantors") and FIRST UNION
NATIONAL BANK, a national banking corporation, as Trustee (the "Trustee") (all
terms used herein without definition having the meanings ascribed to them in the
1997 Indenture).

     The undersigned hereby agrees that:

     1. The undersigned is a Guarantor under the 1997 Indenture with all of the
rights and obligations of the Guarantors thereunder.

     2. The undersigned has granted, ratified and confirmed, in the form and
substance of Exhibit B to the 1997 Indenture, the Guarantee provided for by
Article XI of the 1997 Indenture.

     3. The undersigned hereby represents and warrants that the representations
and warranties set forth in the 1997 Indenture, to the extent relating to the
undersigned as Guarantor, are correct on and as of the date hereof.

     4. All notices, requests and other communications provided for in the 1997
Indenture should be delivered to the undersigned at the following address:

        Keith A. Istre
        Vice President - Finance and
        Chief Financial Officer
        Lamar Media Corp. and its Subsidiaries
        5551 Corporate Blvd.
        Baton Rouge, LA 70808

     5. A counterpart of this Supplemental Indenture may be attached to any
counterpart of the 1997 Indenture.

     6. This Supplemental Indenture shall be governed by and construed in
accordance with the internal laws of the State of New York.

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     IN WITNESS WHEREOF, the undersigned have caused this Supplemental Indenture
to be duly executed as of the day and year first above written.

                                       Guarantor:

                                       Lamar Ohio Outdoor Holding Corp.
                                       an Ohio 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:

FIRST UNION NATIONAL BANK, as Trustee

By: /s/ James Long
    ---------------------------------
Title: Assistant Vice President
       ------------------------------

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                        Additional Subsidiary Guarantors

Lamar KYO, Inc.

Lamar Oklahoma Holding Company, Inc.

Lamar I-40 West, Inc.

Lamar Benches, Inc.

Lamar Advertising of Oklahoma, Inc.

LC Billboard, L.L.C.

Lamar Wright Poster Corp.

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                                                                     EXHIBIT 4.3

                             SUPPLEMENTAL INDENTURE

                                       OF

                                    GUARANTOR

     THIS SUPPLEMENTAL INDENTURE dated as of August 8, 2000, is delivered
pursuant to Section 10.04 of the Indenture dated as of September 25, 1997 (as
heretofore or hereafter modified and supplemented and in effect from time to
time, the "Indenture") among LAMAR MEDIA CORP., a Delaware corporation, certain
of its subsidiaries ("Guarantors") and STATE STREET BANK AND TRUST COMPANY, a
Massachusetts banking corporation, as Trustee ("Trustee") (all terms used herein
without definition having the meanings ascribed to them in the Indenture).

     The undersigned hereby agree that:

     1. The undersigned is a Guarantor under the Indenture with all of the
rights and obligations of Guarantors thereunder.

     2. The undersigned hereby grants, ratifies and confirms the guarantee
provided for by Article Ten of the Indenture to guarantee unconditionally,
jointly and severally with the other Guarantors, to each Holder of a Note
authenticated and delivered by the Trustee, and to the Trustee on behalf of such
Holder, the due and punctual payment of the principal of (and premium, if any)
and interest on such Note when and as the same shall become due and payable.

     3. The undersigned hereby represents and warrants that the representations
and warranties set forth in the Indenture, to the extent relating to the
undersigned as Guarantor, are correct on and as of the date hereof.

     4. All notices, requests and other communications provided for in the
Indenture should be delivered to the undersigned at the address specified in
Section 12.02 of the Indenture.

     5. A counterpart of this Supplemental Indenture may be attached to any
counterpart of the Indenture.

     6. This Supplemental Indenture shall be governed by and construed in
accordance with the laws of the State of New York.

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     IN WITNESS WHEREOF, the undersigned has caused this Supplemental Indenture
to be duly executed as of the day and year first above written.

                                       Guarantor:

                                       Lamar Ohio Outdoor Holding Corp.
                                       an Ohio 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:

STATE STREET BANK AND TRUST
      COMPANY, as Trustee

By: /s/ Andrew Sinasky
    ----------------------------
Title: Assistant Vice President
       -------------------------

                                       2

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                        Additional Subsidiary Guarantors

Lamar KYO, Inc.

Lamar Oklahoma Holding Company, Inc.

Lamar I-40 West, Inc.

Lamar Benches, Inc.

Lamar Advertising of Oklahoma, Inc.

LC Billboard, L.L.C.

Lamar Wright Poster Corp.

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