Annapolis is the capital of the U.S. state of Maryland, as well as the county seat of Anne Arundel County. Situated on the Chesapeake Bay at the mouth of the Severn River, 25 miles (40 km) south of Baltimore and about 30 miles (50 km) east of Washington, D.C., Annapolis is part of the Baltimore–Washington metropolitan area. Its population was measured at 38,394 by the 2010 census.