Each chamber has a sergeant at arms who serves as the chief law enforcement officer and protocol officer.
The Capitol Visitor Center is the main entrance and security checkpoint for the Capitol.
The Capitol building has 540 rooms and has 658 windows
(108 in the dome alone).
The Dome is 8,909,200 pounds of cast-iron with 108 windows, and was constructed between 1855 and 1866. The statue at the top of dome is the Statue of Freedom.
The Rotunda stands 180 feet, 3 inches tall and is 96 feet in diameter.
Paintings and sculptures depicting significant people and events in US history are on display. This room is where presidents and distinguished citizens lie in state.
National Statuary Hall used to be the chambers for the House of Representatives, called the Old Hall of the House (1809-1857). The hall holds 100 of the Capitol's collection of statues of notable citizens in US history, two per state.
The Brumidi Corridors are named after the artist, Constantino Brumidi, who designed the murals along the walls.
Visitor areas on the ground floor include the Hall of Columns, the Brumidi Corridors, the Old Supreme Court Chamber and the Crypt (historical exhibits are presented here).
The Senate chambers are in the north wing and chambers for the House of Representatives and the offices of Congressional leaders are in the south wing.
The third floor has visitors' areas where they may watch proceedings.
The Capitol Complex includes include the Capitol, Capitol Visitor Center, Senate Office Buildings, House Office Buildings, US Supreme Court,
Library of Congress, US Botanic Garden and Capitol Campus grounds.
The Capitol Complex is maintained by the Architect of the Capitol (AOC).
The first AOC was Dr. William Thornton in 1793.
September 18, 1793 - The cornerstone is laid by President George Washington.
1800 - Congress moves from Philadelphia to the new Capitol building in Washington. Only the north wing is complete.
1801 - Supreme Court holds first meeting in the Capitol.
1814 - The Capitol is burned by British troops.
1819 - The Supreme Court, Senate and House meet in newly reconstructed rooms in the Capitol.
1829 - Building reconstruction is completed.
1851 - President Millard Fillmore appoints Thomas U. Walter as the main architect to build extensions onto to the Capitol.
1857 - The House of Representatives holds its first session in its new hall.
1859 - The Senate holds its first session in its new chamber.
1863 - The Statue of Freedom is raised into place atop the dome.
1870 - Exteriors of Capitol extensions are completed.
1890-1900 - Electric lighting is installed throughout building and grounds.
1897 - The Library of Congress moves into its first building (later named the Thomas Jefferson Building).
1935 - The US Supreme Court moves into its own building.
1949-1951 - The House and Senate chambers are redesigned and remodeled.
March 1, 1954 - Five members of the House of Representatives are shot on the House floor
; Alvin Bentley, (R-MI), Ben Jensen (R-IA), Clifford Davis (D-TN), George Fallon (D-MD) and Kenneth Roberts (D-AL). Four Puerto Rican nationalists, Lolita Lebron, Rafael Cancel Miranda, Andres Figueroa Cordero and Irving Flores Rodriguez, are arrested and sent to prison. The shooters were heard shouting, "Freedom for Puerto Rico," as they fired. This incident ends up changing the security measures at the Capitol.
1958-1962 - East front addition to the Capitol.
July 24, 1998 - Gunman, Russell Eugene Weston Jr., fires shots in the Capitol building killing two US Capitol Police officers: Jacob Chestnut, an 18-year veteran and Detective John Gibson, an 8-year veteran. Angela Dickerson is injured during the attack.
October 30, 2003 - Shortly after 1 p.m., US Capitol Police perceive the image of a .38-caliber revolver on an X-ray machine, causing the entire building to be evacuated. The image is later determined to be a toy gun, part of a Halloween costume.
December 2, 2008 - The latest addition to the Capitol, the Visitor Center, opens. The Center is nearly 3/4 the size of the Capitol and is located underground.
April 24, 2009 - The Capitol is briefly evacuated and the White House temporarily locked down when a single-engine plane accidentally wanders into restricted airspace over Washington.
May 13, 2010 -
President Barack Obama appoints Stephen T. Ayers to a 10-year term as the Architect of the Capitol.
October 2013 -
The Architect of the Capitol's office announces that the US Capitol Dome Restoration Project
is ready to begin.
January 14, 2015 -
FBI agents arrest 20-year-old Christopher Lee Cornell before he could move on his plan to attack the US Capitol during the State of the Union address.
The plan was to set off pipe bombs to put lawmakers and employees in panicked flight, and then gun them down with an assault rifle as they ran across his path and that of an accomplice, Special Agent T.A. Staderman wrote. Cornell later pleads guilty on three federal charges.
April 15, 2015 - A Florida man flies a gyrocopter
undetected through restricted airspace and lands on the West Lawn of the Capitol.