Bitterroot National Forest spans 1.587 million acres across west-central Montana and eastern Idaho, ranging from river bottoms to Trapper Peak in the Bitterroot and Sapphire Mountains. Its history includes Lewis and Clark’s passage in 1805, mining booms after gold discoveries in the 1860s, and conservation efforts that led to the Bitter Root Forest Reserve in 1898, later becoming Bitterroot National Forest in 1908. About half the forest lies in wilderness areas where development is barred, while much of the rest remains undeveloped. Known for steep canyons, extensive trails, rich fisheries, and abundant wildlife, it remains a working public landscape and protected mountain backcountry.