[Code of Federal Regulations] [Title 23, Volume 1] [Revised as of April 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 23CFR750.104] [Page 355] TITLE 23--HIGHWAYS CHAPTER I--FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PART 750_HIGHWAY BEAUTIFICATION--Table of Contents Subpart A_National Standards for Regulation by States of Outdoor Advertising Adjacent to the Interstate System Under the 1958 Bonus Program Sec. 750.104 Signs that may not be permitted in protected areas. Erection or maintenance of the following signs may not be permitted in protected areas: (a) Signs advertising activities that are illegal under State or Federal laws or regulations in effect at the location of such signs or at the location of such activities. (b) Obsolete signs. (c) Signs that are not clean and in good repair. (d) Signs that are not securely affixed to a substantial structure, and (e) Signs that are not consistent with the standards in this part.