36 CFR 5.3 : Parks, Forests, And Public Property (§ 1.1 To Parts 1601-1699) — (§ 1.1 To Parts 80-199) — National Park Service, Department Of The Interior (§ 1.1 To Parts 80-199) — Commercial And Private Operations (§ 5.1 To § 5.14) — Business operations.

Engaging in or soliciting any business in park areas, except in accordance with the provisions of a permit, contract, or other written agreement with the United States, except as such may be specifically authorized under special regulations applicable to a park area, is prohibited.