16 U.S. Code § 402d - Extension of boundaries; laws applicable
For the purpose of preserving in their natural state the outstanding scenic features to the south and west of Bryce Canyon National Park, the President of the United States is authorized, upon the joint recommendation of the Secretaries of Interior and of Agriculture, to add to the Bryce Canyon National Park, in the State of Utah, by Executive proclamation, any or all of unsurveyed townships 37 and 38 south, range 4 west, Salt Lake meridian, not included in said park, on June 13, 1930, and all the lands added to said park pursuant hereto shall be, and are, made subject to all laws, rules, and regulations applicable to and in force in the Bryce Canyon National Park.
Source(June 13, 1930, ch. 480, § 1,46 Stat. 582.)