It shall be unlawful for any person to operate an off-highway vehicle in the City, except in those areas specifically designated by the city council for such use. Unless such area is posted with a permanent sign structure, it shall be illegal to operate an off-highway vehicle in such an area. It shall be no defense to a person charged with violating this section that at one time a sign was posted but is no longer standing due to the destruction of such sign. The following area is designated an off-highway vehicle area: none. (Code 1979, § 37-73; Ord. No. 95-86, exhibit A (§ 37-73), 10-9-1995)