Craters of the Moon National Monument and Preserve is a U.S. national monument and national preserve in the Snake River Plain in central Idaho. It is along US 20, between the small towns of Arco and Carey, at an average elevation of 5,900 feet above sea level.
The Monument was established on May 2, 1924. In November 2000, a presidential proclamation by President Clinton greatly expanded the Monument area. The 410,000-acre National Park Service portions of the expanded Monument were designated as Craters of the Moon National Preserve in August 2002. It spreads across Blaine, Butte, Lincoln, Minidoka, and Power counties.
Wikipedia https://en.wikipedia.org/wiki/Craters_of_the_Moon_National_Monument_and_Preserve
Coordinates 43°9'9.908" N -113°28'58.569" E