Centennial Trail State Park, State park with paved trail in Spokane County, Washington

Centennial Trail State Park is a recreation area with a paved path that runs along the Spokane River in Washington. The trail passes through pine forests and rocky canyon areas, connecting two major points on opposite sides of the county.

After Expo '74, advocates proposed a mixed-use path along the Spokane River. By 1986 citizens in Washington and Idaho had joined forces and suggested a much longer trail, timed to mark the state centennials of Washington (1989) and Idaho (1990). It was designated a National Recreation Trail in 2010.

The trail's name marks the state centennials of Washington (1989) and Idaho (1990), the deadlines citizens of both states set when they proposed a long riverside route in 1986. After the border crossing under the Interstate 90 Spokane River Bridge, the path continues as the North Idaho Centennial Trail, so the name carries on into the neighbouring state.

The trail runs 39 miles (63 km) from Nine Mile Boat Launch in Nine Mile Falls to the Washington–Idaho border, where it meets the North Idaho Centennial Trail. It is divided into Riverside, Urban and Valley sections, so you can pick a stretch to suit your trip. The asphalt surface with concrete curbing suits walking and cycling; a black lamppost and a metal trash can stand along the path.

The trail crosses into Idaho for about 250 feet (76 m) beneath the Interstate 90 Spokane River Bridge, then returns to Washington for roughly 2,000 feet before meeting the North Idaho Centennial Trail at the state line. The route is split into Riverside, Urban and Valley sections, and in 2010 it was designated a National Recreation Trail.