United States Capitol subway system

The subway system of the United States Capitol in Washington, D.C., consists of three underground electric people mover systems that connect the United States Capitol to all three of the Senate office buildings and one of the four House office buildings.

The original subway line was built in 1909 to link the Russell Senate Office Building to the Capitol. In 1960, an operator-controlled monorail was installed for the Dirksen Senate Office Building. A two-car subway line connecting the Rayburn House Office Building to the Capitol was built in 1965. The Dirksen monorail, which had been extended to the Hart Senate Office Building in 1982, was replaced in 1993 by an automatic train.

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