The major north-south highway, U.S. 195 provides access for the Clarkston-Lewiston, Pullman-Moscow and Colfax areas to Interstate 90 in Spokane. The major east-west highway, U.S. 12 traverses the width of the District through the lower three counties of Asotin, Garfield and Columbia . U.S. 12 connects U.S. 195 on the east to major highways I-84 and U.S. 395 west of the District.

There are also a number of state highways, which serve as feeders into the population centers and as links between the smaller communities of the area. Many of these roads can be categorized as internal, in that their origin and terminus are within the District. A major exception to this is State Route 26, which runs west from Colfax and connects with Interstate 90 at Vantage. This is a major route west to Seattle. State Highway 129 is the major north-south highway between Clarkston and Enterprise, Oregon.

MAJOR HIGHWAYS IN THE PALOUSE ECONOMIC DEVELOPMENT COUNCIL AREA (Click to enlarge map)

SUMMARY OF ROADWAY MILEAGE BY JURISDICTION, WA