The U.S. Capitol Rotunda.
The United States Capitol rotunda is the central rotunda of the United States Capitol in Washington, D.C.. Located below the Capitol dome, it is the tallest part of the Capitol and has been described as its "symbolic and physical heart."
The rotunda is surrounded by corridors connecting the House of Representatives and Senate sides of the Capitol. To the south of the rotunda is the semi-circular National Statuary Hall, which until 1857 was the House of Representatives chamber. To the northeast of the rotunda is the Old Senate Chamber, used by the Senate until 1859 and by the Supreme Court of the United States until 1935.
The rotunda is 96 feet (29 m) in diameter and rises 180 feet 3 inches (54.94 m) to the canopy, and is visited by thousands of people each day. It is surmounted by the American Statue of Freedom. And it is also used for ceremonial events authorized by concurrent resolution, including the lying in state of honored people.