Washington, D.C., formally the District of Columbia and commonly referred to as Washington, “the District”, or simply D.C., is the capital of the United States. The signing of the Residence Act on July 16, 1790, approved the creation of a capital district located along the Potomac River on the country’s East Coast. As permitted by the U.S. Constitution, the District is under the exclusive jurisdiction of the United States Congress and is therefore not a part of any U.S. state. The states of Maryland and Virginia each donated land to form the federal district, which included the preexisting settlements of Georgetown and Alexandria; however, Congress returned the Virginia portion in 1846. Named in honor of George Washington, the City of Washington was founded in 1791 to serve as the new national capital. Congress created a single municipal government for the whole District of Columbia after the American Civil War.
Washington, D.C., had an estimated population of 632,323 in 2012, the 24th most populous place in the United States. Commuters from the surrounding Maryland and Virginia suburbs raise the city’s population to more than one million during the workweek. The Washington Metropolitan Area, of which the District is a part, has a population of 5.7 million, the seventh-largest metropolitan area in the country. The centers of all three branches of the federal government of the United States are in the District, including the Congress, President, and Supreme Court. Washington is home to many national monuments and museums, which are primarily situated on or around the National Mall. The city hosts 176 foreign embassies as well as the headquarters of many international organizations, trade unions, non-profit organizations, lobbying groups, and professional associations.
Outside downtown Washington, architectural styles are even more varied. Historic buildings are designed primarily in the Queen Anne, Châteauesque, Richardsonian Romanesque, Georgian revival, Beaux-Arts, and a variety of Victorian styles. Rowhouses are especially prominent in areas developed after the Civil War and typically follow Federalist and late Victorian designs. Georgetown’s Old Stone House was built in 1765, making it the oldest-standing original building in the city. Founded in 1789, Georgetown University features a mix of Romanesque and Gothic Revival architecture. The Ronald Reagan Building is the largest building in the District with a total area of approximately 3.1 million square feet (288,000 m2).
