Rather than being state wide or parish wide, a law may only apply to a special area or zone. Here is an example from New Orleans:
Sec. 106-2. - Bicycle speed limit in Audubon Park; lights.
(a) It shall be unlawful for any person to operate a bicycle at a speed in excess of ten miles per hour in that portion of Audubon Park bounded by Magazine Street, Exposition Blvd., St. Charles Avenue and Walnut Street.
(b) All bicycles operating in the abovementioned area shall possess a working light when used in either pre-sunrise or post-sunset periods.
(Code 1956, § 42-116)
And here is one from Baton Rouge:
Sec. 11:232. - Freestyle skateboarding, bicycling, and roller skating prohibited on park structures.
It shall be unlawful for any person to use, operate or ride any skateboard, bicycles or roller skates on or upon structures and site furnishings of North Boulevard Town Square, Repentance Park, Riverfront Plaza and Riverfront Landing Facility, Maritime Plaza, the Baton Rouge River Center Plaza, City Hall Building and Plaza, Florida Street Levee Access Plaza, Baton Rouge City Court Building, Municipal Building, 19th Judicial District Courthouse and the east and west high-rise parking garages in the city.
(Ord. No. 8669, § 1, 6-8-88; Ord. No. 10940, § 1, 7-23-97; Ord. No. 15673, § 1, 4-9-14)