National Park Service Website | Monument Management Plans

 

The Monument is a geologic wonder cast in a wild and remote landscape. Its central focus is the Great Rift, a 62-mile long crack in the earth's crust.  The Great Rift is the source of a remarkably preserved volcanic landscape with an array of exceptional features.  Craters, cinder coves, lava tubes, deep cracks, and vast lava fields form a strangely beautiful volcanic sea on central Idaho's Snake River Plain. Located in central Idaho, approximately 160 miles east of Boise, the Monument was established in 1924 by President Coolidge. It was expanded in 2000 and now includes 661,000 additional acres of federal land, which are jointly managed by the BLM and National Park Service.