Olympia Regional Airport is a public use airport located four nautical miles (7 km) south of the central business district of Olympia, a city in Thurston County and the capital of the U.S. state of Washington. It is owned by the Port of Olympia. It is about one mile (1.6 km) east of Interstate 5, actually within the boundaries of the city of Tumwater which is south of and adjacent to Olympia. The airport was identified in the Washington State Department of Transportation Long Term Aviation Study as a field that could potentially serve to relieve Seattle-Tacoma International Airport of increasing congestion.