Washington Union Station is a major train station, transportation hub, and leisure destination in Washington, D.C. Opened in 1907, it is Amtrak's headquarters and the railroad's second-busiest station with annual ridership of just under 5 million. The station also serves MARC and VRE commuter rail services, the Washington Metro, and buses. At the height of its traffic, during World War II, as many as 200,000 passengers passed through the station in a single day.