1966 Map of Big Hole Pass

About this map

The Continental Divide snake along the high ridgelines of the Beaverhead Mountains, serving as the natural boundary between Lemhi County, Idaho, and Beaverhead County, Montana. This mid-century survey reveals a landscape defined by its mining and backcountry history, where a Pack Trail winds through the high-altitude terrain to cross at Big Hole Pass. Local exploration is evidenced by multiple prospects and name-driven landmarks like Morgan Mtn and Eagle Mtn. Drainage systems like Dahlonega Creek and West Fork Rabbit Creek flow from these heights into the surrounding Salmon National Forest and Beaverhead National Forest. The presence of Morgan Jones Lake and the various gulches, such as Bradley Gulch and Thompson Gulch, illustrates the water-driven erosion patterns of the northern Rockies before modern development altered these remote territories.