Metrorail, often referred to as the Metro, is the public subway system in Washington, D.C., owned by the Washington Metropolitan Area Transit Authority (WMATA), a government agency established by interstate compact between the District of Columbia, Maryland and Virginia, with the approval of Congress. It is governed by a Board of Directors whose members are appointed by the D.C. City Council, the Northern Virginia Transportation Commission, and the Washington Suburban Transit Commission. The compact was later amended to include representatives of the federal government, and of the Governors of Virginia and Maryland.
Metrorail began operations in 1976. The subway system consists of six "lines": the Red, Orange, Green, Blue, Yellow and Silver lines. This makes maps easy to follow visually, although some color-blind passengers have experienced problems differentiating between some of the colors. The stations and trains are known for being clean and tidy. WMATA also operates a bus system known as Metrobus.