Segment of the northern Rocky Mountains , U.S. Extending north-south 300 mi (480 km) along the Idaho-Montana border, its peaks average about 9,000 ft (2,700 m); Idaho's Scott Peak is the highest, at 11,393 ft (3,473 m).
Owing to the mountains' inaccessibility from the east, the Lewis and Clark Expedition (1805) had to travel north more than 100 mi (160 km) to find a route through the range. Bitterroot National Forest extends across the centre of the range.