The United States Capitol, located on Capitol Hill in Washington, D.C., is the seat of the U.S. Congress, the legislative branch of the federal government. It has housed the meeting chambers of the Senate and the House of Representatives since 1800, serving as a symbol of American democracy and government.
It contains about 540 rooms, 658 windows (108 in the dome), and around 850 doorways.
 
interesting fact...
in 2025 Congressman Tim Moore discovered a secret tunnel outised the Capitol which leads underneath it. it actulaly leads to the Lincoln Room where Abe would have sat next to the fireplace.