District of Columbia

District of Columbia, federal district of the United States, coextensive with the city of Washington, D.C., the national capital. It is situated on the Potomac and Anacostia rivers and has an area of about 177 sq km (68 sq mi).

Government departments and agencies are the major source of employment in the District. Other important industries are tourism, including the convention trade; scientific research and development; and the manufacture of technical equipment. The District is well known for its cultural institutions, historic landmarks, and parks.

Bills passed by the US Congress in 1790-1791 created the District on a tract of land ceded by Maryland and Virginia. The area contained the communities of Alexandria and Washington. The cornerstone of the US Capitol was laid in 1793, and in 1800 Congress moved here from its temporary headquarters in Philadelphia. In 1847, Alexandria and the remainder of the District on the western bank of the Potomac were returned to the state of Virginia by an act of Congress. Georgetown held the status of a separate town within the District from 1878 to 1895, when it was merged with Washington. Population (1980) 638,432; (1990) 606,900.