Mount Vernon Square station is a Washington Metro station in Washington, D.C., on the Green and Yellow Lines. It is the northeastern terminus of the Yellow Line.

The Washington Metro, often abbreviated as the Metro and formally the Metrorail, is a rapid transit system serving the Washington metropolitan area of the United States. It is administered by the Washington Metropolitan Area Transit Authority (WMATA), which also operates the Metrobus service under the Metro name. Opened in 1976, the network now includes six lines, 98 stations, and 129 miles (208 km) of route.