In 1966, the United States Congress created the Washington Metropolitan Area Transit Authority (WMATA) to take control of the District's private bus system and develop a new Metro network for the Nation's capital. Following extensive planning, construction of Washington's Metrorail transit system started in 1969. Seven years later, revenue service began on a 7-kilometre line section with five stations in operation. Another 25 years later, in 2001, the originally planned Washington Metrorail system, shown in Figure 1, was completed, reaching a total of 166 kilometres with 83 stations.