54 U.S.C. § 100101 — Promotion and regulation

(a) In General. The Secretary^* of the Interior, acting through the Director^* of the National Park Service^*, must promote and regulate use of the National Park System^*. Every rule and action must fit the System's fundamental purpose: to conserve the scenery, and the natural and historic objects and wildlife, in the System's units — and to let people enjoy that scenery, those objects, and that wildlife — in ways that leave them unimpaired for future generations to enjoy.

(b) Declarations.
(1) 1970 declarations. Congress declares that: (A) the National Park System^*, which began with Yellowstone National Park in 1872, has grown to include outstanding natural, historic, and recreational areas across every major region of the United States and its territories and possessions; (B) though each area is distinct, their related purposes and resources unite them into one National Park System, expressing one shared national heritage; (C) being included together in one System, managed for the benefit and inspiration of all Americans, gives these areas added national importance and recognition of their outstanding environmental quality; and (D) this division's purpose is to include all these areas in the System, and to clarify the legal authorities that apply to it.
(2) 1978 reaffirmation. Congress reaffirms, declares, and directs that promoting and regulating the System's units must be consistent with, and grounded in, the purpose set out in subsection (a), for the common benefit of all Americans. Any authorized activity must be interpreted, and the System's protection, management, and administration must be carried out, in light of the System's high public value and integrity. None of this may be done in a way that undercuts the values and purposes for which the System's units were established — except when Congress directly and specifically allows it.