Borah Peak, also called Mount Borah or Beauty Peak, is Idaho’s highest mountain, rising in the Lost River Range within Challis National Forest and standing among the most prominent peaks in the contiguous United States. In 2021, the U.S. Geological Survey recognized it as the site of Idaho’s only active glacier. Named in 1934 for longtime U.S. senator William Borah, the mountain is also tied to the powerful 1983 earthquake that lifted the peak, dropped the nearby valley, and left a visible scar. Its steep routes, exposed ridges, snow, and avalanche danger have made it Idaho’s best-known and one of its most hazardous summits.