Photos of the U.S. Capitol Building in Washington, DC

The dome of the U.S. Capitol was constructed between 1855 and 1866. It is made of cast iron and was designed by the Philadelphia architect Thomas U. Walter, who was also the architect of the House and Senate extensions.

The Rotunda is the interior of the Capitol Dome, a large circular room that is used for ceremonial functions, such as the unveiling of statues, inaugurations, and the lying in state of past presidents. A "frieze," depicts significant events in American history on the upper walls and the lower walls are decorated with historic paintings.

This room was the Old Hall of the House, the meeting room for the House of Representatives prior to the completion of their current chambers. In 1864, Congress invited each state to contribute two statues of prominent citizens for permanent display in this room and renamed it the National Statuary Hall.

The U.S. Supreme Court was located in the Capitol Building until 1935. This room was used by the Court between 1810 and 1860.

The Crypt, located on the Capitol's first floor beneath the Rotunda, serves to display sculpture and interpretive exhibits. Despite its name, the Crypt has never been used as a burial vault.

The Statue of Freedom, by Thomas Crawford, sits atop the dome of the United States Capitol. The statue is a classical female figure, standing on a cast-iron globe encircled with the words E Pluribus Unum, Latin for "Out of Many, One," which originally suggested that out of many colonies or states emerge a single nation. Over time these words have come to suggest that out of many races and ancestries has emerged a single nation. The Statue of Freedom stands 19 feet 6 inches tall and weighs approximately 15,000 pounds.

Today, the Capitol is part of a complex that includes three major office buildings, one annex building for the House of Representatives and three major office buildings for the Senate. See a map of the Capitol.

The 19th-century neoclassical architecture is very impressive when the Capitol Dome is illuminated at night.

More than 3 million visitors tour the U.S. Capitol each year. The Capitol Grounds comprise of 274 acres with manicured lawns, walkways, and gardens. Tours are free and a great way to learn about our nation's history. ​Visit the Capitol Visitor Center to begin your exploration.