Built on a hill popularly called Capitol Hill in Washington, D.C., the U.S. Capitol has been the home of the House of Representatives and the Senate since 1800.

President George Washington and Secretary of State Thomas Jefferson began the project with a design contest in March, 1792, and eventually rejected all 17 proposals that were submitted. Six months later, William Thornton, a doctor and amateur architect from the British West Indies, requested consideration of his late proposal. Washington approved the plan, noting its "grandeur, simplicity and convenience."

An example of 19th Century neoclassical architecture, the Capitol has undergone many construction phases over the centuries. It opened for the first session of Congress on Nov. 17, 1800. By 1813, it was complete, except for a temporary wooden passageway between two wings.

British troops burned the building on Aug. 24, 1814. Reconstruction began in 1815 and architects took the opportunity to add new materials such as marble. Cost overruns and construction delays mounted kept the working going through 1829.

Multiple construction projects have since followed. Today, the Capitol covers 175,170 square feet and is the center of six other House and Senate buildings, as well as three Library of Congress buildings.