In order to preserve historic features and sites associated with the Battle of the Big Hole and to facilitate their administration and interpretation, the boundaries of the Big Hole National Battlefield are hereby revised to include the following described lands: montana principal meridian Township 2 south, range 17, west: Section 13, southwest quarter southeast quarter, southeast quarter southwest quarter, east half southwest quarter southwest quarter; section 23, east half northeast quarter southeast quarter; section 24, west half east half, north half southwest quarter, southeast quarter southwest quarter, east half southwest quarter southwest quarter; section 25, those portions of the northeast quarter northwest quarter and the northwest quarter northeast quarter lying north of the north right-of-way line of relocated Montana State Route 43; consisting of approximately 466 acres.
(Pub. L. 88–24, § 2, May 17, 1963, 77 Stat. 18.)