Henderson Mountain is a prominent summit in southern Montana’s Beartooth Mountains, within Custer-Gallatin National Forest and the historic New World Mining District near Cooke City. Its steep slopes divide drainage between Fisher Creek and the Miller Creek–Soda Butte Creek system, and its rugged form reflects a laccolith of Cambrian limestone and breccia intruded by Eocene dacite porphyry in a subarctic climate. The mountain is closely linked to local mining history: gold was discovered there in 1888, and its name honors Bart Henderson, one of four trappers who identified the district in 1869. In the mid-1990s, it also became the focus of a major fight over proposed gold and silver mining near Yellowstone.