It is 40.645 miles (65.41 km) in length and generally runs southwest to northeast SH-6 begins at the Washington state line in Latah County as a continuation of Washington State Route 272, then heads east to an intersection with U.S. 95, with which it briefly overlaps before diverging and continuing east into Potlatch.

SH-6 continues northeast and north across the Palouse River into Benewah County, generally north through White Pine Drive; and area of old-growth white pine trees in the Hoodoo Mountains in the St. Joe National Forest.

[1][2] Between Harvard and Emida, the route crests at an elevation of about 3,600 feet (1,095 m) above sea level.

This is a park 'n' ski lot (Palouse Divide) for cross-country skiing,[3] and the turnoff to North–South Ski Bowl, a defunct alpine area which is now a private conference and retreat lodge.

[4][5] Prior to the 1960s, SH-6 was signed as an alternate route of U.S. 95, which continued north along present-day SH-3.