Getting Oriented
The motorway runs through the Nez Perce-Clearwater and Lolo National Forests in northern Idaho, with Pierce, Idaho near the western access and the Powell, Idaho/Montana border area near the eastern. The route follows the Lolo Trail, a Nez Perce travel route used to cross between the Bitterroot Valley (Montana) and the Clearwater River (Idaho). On September 11, 1805, Lewis and Clark started their crossing here, taking 11 grueling days to cover what is now the road's 95 miles. Sergeant Patrick Gass called it "the most terrible mountains I ever beheld."
Trail Overview
The motorway parallels the modern US-12 (Lewis and Clark Highway) along the high ridges several miles above and to the north of the highway. From the western access at Lolo Pass, the road drops west, climbs again to the divide, and runs roughly parallel to US-12 for the bulk of its length. Single-lane, narrow, and rough — the road's character has changed little since 1930s construction. Average speeds run 5 to 10 miles per hour over rocks, exposed roots, and washouts.
Driving the full motorway takes 8 to 12 hours including stops at the Lewis and Clark interpretive sites. Most travelers split the route into two or three days, camping at one of the dispersed sites or at developed forest service campgrounds.
Points of Interest
- Lolo Pass Visitor Center. At the eastern access on US-12 at the Idaho-Montana border. Interpretive exhibits on Lewis and Clark and the Nez Perce.
- Smoking Place. A site where Lewis and Clark smoked with the Nez Perce on their return journey.
- Indian Post Office. A traditional Nez Perce travel landmark.
- Howard Camp. Site of an 1877 US Army camp during the Nez Perce War.
- Sherman Saddle. A prominent crossing point between drainages.
- Bald Mountain Lookout. Former fire lookout with panoramic views.
- Spring Hill. A high overlook of the Bitterroot Range.
Where to Camp
Dispersed camping is allowed at unmarked pullouts throughout the motorway with the 14-day stay limit. Several developed Forest Service campgrounds sit on US-12 below the motorway and serve as base camps for day trips up. The Wendover Ridge and Powell Ranger Station areas have informal staging.
Tips for a Safe and Enjoyable Trip
- Travel July through September. Snow closes the route October through June most years.
- Plan two or three days. Single-day attempts exhaust drivers and risk night-driving the unsafe road.
- ATVs and motorcycles handle the surface better than full-size vehicles. Both are legal.
- Carry full fuel, water, and food. Recovery gear is essential.
- Carry an offline map. Mileage markers and signage are inconsistent.
- Cell coverage is absent. Carry a satellite messenger.
- Do not damage Lewis and Clark or Nez Perce cultural sites. Federal protection applies.
- Watch for elk, mountain lions, and black bears.
- Contact the Nez Perce-Clearwater National Forests at 208-983-1950 for current conditions.
