The crescent-shaped plain cuts a wide and level swath through an otherwise mountainous state and defines the southern limits of the monument, while the Pioneer Mountain Range bounds it to the north. The monument's 53,545 acres embrace a small portion of the range's foothills and a vast expanse of lava flows to the south. Elevation ranges from 7,700 feet to 5,300 feet, with an elevation at the headquarters of 5,900 feet. For the most part, the monument's relief is low and studded with cinder cones. The average precipitation is seventeen inches a year, mostly in snowfall, which begins in November and generally lasts until April.
Temperatures change dramatically.
In any given month it can freeze. This remote and harsh environment, however, possesses a strange beauty all its own. It is a place where in the high desert air sunlight glances off the twisted, broken, and billowed lava flows and formations in an array of shades and hues that is at once austere and captivating. Twin Falls, Idaho Falls, and Pocatello. Offering a two-hour drive from these locations, the highway also routes tourists between Yellowstone National Park and the region of Sun Valley and the Sawtooth National Recreation Area.