The Sleeping Bear Dunes National Lakeshore (hereinafter referred to as the “lakeshore”) shall comprise the land and water area generally depicted on the map entitled “A Proposed Sleeping Bear Dunes National Lakeshore Boundary Map”, numbered NL–SBD–91,000 and dated May 1969, which shall be on file and available for public inspection in the offices of the National Park Service of the Department of the Interior.

As soon as practicable after October 21, 1970, and following the acquisition by the Secretary of those lands owned by the State of Michigan within the boundaries of the area designated for inclusion in the lakeshore (excepting not to exceed three hundred acres in the Platte Bay area) and of such additional lands, if any, as are necessary to provide an area which in his opinion is efficiently administrable for the purposes of this subchapter, he shall establish the Sleeping Bear Dunes National Lakeshore by publication of notice thereof in the Federal Register.