On September 18, 1793, George Washington laid the cornerstone of the United States Capitol on Jenkins Hill, in a federal city that was still mostly fields and swamp. He arrived in a procession from Georgetown, crossed the Tiber Creek by a temporary bridge, and performed the ceremony in Masonic apron and sash. The crowd was small. There was almost no town to hold a larger one.
The site had been picked by Pierre L'Enfant, who called it a pedestal waiting for a monument, and the competition to design it had been a mess. Nobody liked the entries, and the commissioners were close to giving up when William Thornton, a physician and amateur architect from Tortola, submitted a plan in January 1793, after the deadline, and won. It was for a building with a central dome and two wings, and it was grand enough. Then the work stalled.
It stalled for a decade and more. There was not enough money, not enough skilled labour, and not enough agreement. Congress moved into the north wing in 1800, in a building with a wooden roof over an unfinished chamber, and shared the space with the Supreme Court and the Library of Congress. The south wing was finished in 1811. In August 1814 British troops burned the whole thing, including the library, in reprisal for the American burning of York.
Rebuilding took longer than building. Benjamin Latrobe and then Charles Bulfinch restored the wings by 1819, and by the 1850s the old low dome no longer suited the building's new scale. Thomas Walter designed the cast-iron dome that is there now, and it went up between 1856 and 1866 while the country was at war, on Lincoln's argument that finishing it showed the Union was still functioning. The Statue of Freedom went on top in 1863.
The building has been extended and rebuilt ever since: the terraces in the 1880s, the east front in 1962, a visitor centre underground in 2008. It covers about 16 acres. The cornerstone Washington laid has never been found, and the ceremony has been re-enacted by several presidents since, including one in 1993, on the bicentenary.