Olympia is the capital city of the U.S. state of Washington. It had a population of 55,605 at the 2020 census, making it the state of Washington's 23rd-most populous city. Olympia is the county seat of Thurston County, and the central city for a metropolitan statistical area of 298,758, the fifth-largest in Washington state. Located 50 miles southwest of Seattle, Olympia anchors the South Puget Sound region of Western Washington.