Metrorail is the Washington, D.C. area's regional rail system. Often referred to simply as "Metro," it's one component of the Metro system, which also includes Metrobus and MetroAccess. There are 11 Metrorail stations in Arlington, providing fast, frequent service between Arlington, Washington, and the surrounding areas. Metro's Orange, Silver, Blue, and Yellow lines all serve Arlington. The Metro system is operated by the Washington Metropolitan Area Transit Authority (WMATA).