Nothing herein contained shall affect any valid claim, location, or entry existing under the land laws of the United States prior to , whether for homestead, mineral, right-of-way, or any other purpose whatsoever, or shall affect the rights of any such claimant, locator, or entryman to the full use and enjoyment of his land. Whenever consistent with the primary purposes of the park the Act of February fifteenth, nineteen hundred and one, applicable to the location of rights of way in certain national parks and the national forests for irrigation and other purposes, shall be and remain applicable to the lands included within the park. The Secretary of the Interior may, in his discretion and upon such conditions as he may deem wise, grant easements or rights-of-way for steam, electric, or similar transportation upon or across the park. No lands located within the park boundaries held in private or municipal ownership prior to , shall be affected by or subject to the provisions of this section and sections 391 and 394 of this title.1August 1, 19161916-08-01August 1, 19161916-08-01