Geography of Washington, D.C. in the context of "Massachusetts Avenue (Washington, D.C.)"

The United States Capitol, often called the Capitol or the Capitol Building, is the seat of the United States Congress, the legislative branch of the federal government. It is located on Capitol Hill at the eastern end of the National Mall in Washington, D.C. Although no longer at the geographic center of the national capital, the U.S. Capitol forms the origin point for the street-numbering system of the district as well as its four quadrants. Like the principal buildings of the executive and judicial branches, the Capitol is built in a neoclassical style and has a white exterior.

Central sections of the present building were completed in 1800, when the 6th U.S. Congress convened there on November 17, 1800, moving the national capital from Philadelphia to Washington, D.C.. The building was partly destroyed in the 1814 Burning of Washington by the British, then was fully restored within five years. The building was enlarged during the 19th century, by extending the wings for the chambers for the bicameral legislature as more states were admitted to the union, with the House of Representatives housed in the south wing and the Senate housed in the north wing. The massive dome was completed around 1866 just after the American Civil War. The east front portico was extended in 1958. The building's Visitors Center was opened in the early 21st century.