Lolo Trail is about 100 miles long, roughly from Weippe to beyond Lolo Pass (which is on the Idaho-Montana border). From Lolo, Montana, to a few miles west of Lolo Pass, the trail closely follows U.S. Highway 12. It then follows the high mountain ridges north of the highway for more than 80 miles, eventually descending to the Weippe Prairie near Weippe, Idaho. The corridor of this trail and pass contain significant ethnographic, archeological, and historic resources associated with Nez Perce use during buffalo hunts as well as during the Nez Perce War of 1877. In addition, Lewis and Clark followed this pathway during their expedition. Recreational opportunities, natural quiet, and high air quality are important resources along this trail. Wildlife is also abundant.

The Lolo Trail is a national historic landmark. It encompasses the Nez Perce (Nee-Me-Poo) National Historic Trail and the Lewis and Clark National Historic Trail. Known as the Buffalo Trail in ancient times, this trail was used by the Nez Perce and the U.S. Cavalry in the 1877 war. The Lolo Motorway, closely paralleling the Buffalo Trail, was built by the Civilian Conservation Corps in the 1930s. Although much of the area has been maintained as pristine forest, from higher viewpoints along the trail corridor evidence of clearcuts and other timbering activities are obvious.

The Clearwater National Forest manages the historic trails. A Forest Service Visitor Center (under construction until 2001) on the Idaho/Montana border at Lolo Pass serves as the central information station for the area.