16 U.S.C. § 459b-2
As soon as practicable after August 7, 1961, and following the acquisition by the Secretary of an acreage in the area described in section 459b of this title that is in the opinion of the Secretary efficiently administrable to carry out the purposes of sections 459b to 459b-8 of this title, the Secretary shall establish Cape Cod National Seashore by the publication of notice thereof in the Federal Register.
Such notice referred to in subsection (a) of this section shall contain a detailed description of the boundaries of the seashore which shall encompass an area as nearly as practicable identical to the area described in section 459b of this title. The Secretary shall forthwith after the date of publication of such notice in the Federal Register (1) send a copy of such notice, together with a map showing such boundaries, by registered or certified mail to the Governor of the Commonwealth of Massachusetts and to the board of selectmen of each of the towns referred to in section 459b of this title; (2) cause a copy of such notice and map to be published in one or more newspapers which circulate in each of such towns; and (3) cause a certified copy of such notice, a copy of such map, and a copy of sections 459b to 459b-8 of this title to be recorded at the registry of deeds for Barnstable County, Massachusetts.
16 U.S.C. § 459b-2