Centennial Trail State Park is a 37 mile paved trail, managed by Riverside State Park. The park consists of a paved trail meandering along the Spokane River and extending from Nine Mile Falls to the Idaho state line. The trail was dedicated and named the Centennial Trail in 1989, in commemoration of Washington state’s 100th birthday that year. The trail contains interpretive signs and 42 historical sites, most of which remain unmarked.