Continuing north, the US‑93 runs along portions of the Lewis and Clark Trail. The highway follows the descending northbound river until North Fork at , where the Salmon River makes a left turn to flow west across the state to Riggins. U‑93 continues north, climbing the North Fork of the Salmon River into the Bitterroot Range, passing through the Salmon-Challis National Forest and Gibbonsville. The highway exits Idaho at Lost Trail Pass (web-cam) at and enters Montana toward the Bitterroot Valley. West of the highway at the pass is the Lost Trail Powder Mountain ski area, with terrain in both states.