On Sept. 13, 1805, the Lewis and Clark party crossed this pass westbound for the Pacific after a long detour to the south. From the headwaters of the Missouri they had crossed the mountains to the Salmon. Finding that river impassable, they traded for pack horses, hired an Indian guide, and came north to an Indian trail across the mountains here. Tired and ill-fed, the men were to have a hard struggle in early snow along the steep ridges which the trail followed for most of the 125 mile course west to the Clearwater River.