1956 Map of Cooper Gulch

About this map

Thompson Pass serves as a critical geographic gateway along the high border between Montana and Idaho, marking a point where the Shoshone and Sanders county line meets the state boundary. This mid-century survey reveals a landscape largely defined by federal management, as the Kaniksu, Lolo, and Coeur d'Alene National Forests all converge here. While the terrain is dominated by high points like Dixie Peak and Haystack Mountain, human activity is etched into the landscape through the presence of the Montana Mine and a USFS Fire Station. The map captures the hydrological network of the Bitterroot Range, from the headwaters of Prichard Creek to the high-elevation Blossom Lakes and Upper Glidden Lake. The presence of U.S. 10-A indicates the primary transit route through this wilderness, providing access to the various gulches and ridges that shaped the region's early mining and forestry history.