Which city became the permanent capital of the United States in 1800?

Washington, D.C., became the permanent capital of the United States in 1800.

The Constitution authorized a federal district that would not belong to any state. In 1790, the Residence Act selected a site on the Potomac River, reflecting a political compromise between regional interests. The district was named for George Washington, and the planned capital was designed by Pierre Charles L’Enfant.

The federal government moved from Philadelphia to Washington in 1800. John Adams became the first president to live in the unfinished President’s House, later called the White House, while Congress met in the partially completed Capitol.

Several cities had served as temporary national capitals during the Revolutionary era and the Confederation period. New York City was the first capital under the Constitution, and Philadelphia served as the capital before Washington’s permanent federal district opened.