Spokane is a city in and the county seat of Spokane County in the U.S. state of Washington. It lies along the Spokane River, adjacent to the Selkirk Mountains and west of the Rocky Mountain foothills, 110 miles (180 km) south of the Canada–United States border, twenty miles (30 km) west of the Idaho border, and 280 miles (450 km) east of Seattle, via Interstate 90.