The Washington Metro, commonly called Metro and branded Metrorail, is the rapid transit system serving the Washington, D.C. metropolitan area in the United States. It is administered by the Washington Metropolitan Area Transit Authority (WMATA), which also operates Metrobus service under the Metro name. Besides the District, Metro serves several jurisdictions in Maryland and Virginia. In Maryland, Metro provides service to Montgomery and Prince George's counties; in Virginia, to Fairfax and Arlington counties and the independent cities of Alexandria, Fairfax and Falls Church. The system is currently being expanded into Loudoun County, Virginia. The Metro service area is largely coextensive with the inner ring of the Washington metropolitan area. Opened in 1976, the network has grown to include six lines, 91 stations, and 117 miles (188 km) of route.