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                                                                 EXHIBIT 5.1

                       [PALMER AND DODGE LLP LETTERHEAD]



                                                              February 10, 2000

Lamar Advertising Company
5551 Corporate Boulevard
Baton Rouge, Louisiana 70808


         We are rendering this opinion in connection with the Registration
Statement on Form S-4 (the "Registration Statement") filed by Lamar Advertising
Company (the "Company") with the Securities and Exchange Commission under the
Securities Act of 1933, as amended, on or about the date hereof. The
Registration Statement relates to the registration of shares (the "Class A
Shares") of the Company's Class A Common Stock, $0.001 par value, having an
aggregate value of $183,060,071.06.

         We have acted as your counsel in connection with the preparation of the
Registration Statement and are familiar with the proceedings taken by the
Company in connection with the authorization and issuance of such Class A
Shares. We have examined all such documents as we consider necessary to enable
us to render this opinion.

         Based upon the foregoing, we are of the opinion that the Company has
the authority pursuant to its Certificate of Incorporation, as amended, to issue
up to 125,000,000 shares of Class A Common Stock; upon adoption by the Board of
Directors of the Company of a resolution in form and content as required by
applicable law and upon issuance and delivery of and payment for such Class A
Shares in the manner contemplated by the Registration Statement, the Prospectus
and any related Prospectus Supplement(s) and by such resolution, such Class A
Shares will be validly issued, fully paid and nonassessable.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under "Legal Matters."

                                Very truly yours,

                                /s/ Palmer & Dodge LLP





