The administration, protection, and promotion of said Badlands National Park shall be exercised under the direction of the Secretary of the Interior by the National Park Service, subject to the provisions of the Act of August 25, 1916, entitled “An Act to establish a National Park Service, and for other purposes,” as amended by the Act of June 2, 1920 (Forty-first United States Statutes at Large, page 732): 1 Provided, That in advance of the fulfillment of the conditions herein the Secretary of the Interior may grant franchises for hotel and for lodge accommodations under the provisions of this section.