Alexandria is bisected north and south by State Route 7, known in most of the city as the major thoroughfare of King Street. Interstate 95/495 (the Capital Beltway), including the Woodrow Wilson Bridge over the Potomac River, approximately parallels the city's southern boundary with Fairfax County. Interstate 395 crosses through the western part of the city. Other major routes include U.S. 1 (named Jefferson Davis Highway, and Patrick and Henry Streets after Patrick Henry, and Richmond Highway), the George Washington Memorial Parkway, and Duke Street (State Route 236).
Alexandria is located just south of Ronald Reagan Washington National Airport in Arlington County. As with other Washington suburbs, Alexandria is also served by Washington Dulles International Airport in Sterling, Virginia and by Baltimore-Washington International Thurgood Marshall Airport near Baltimore, Maryland. Southbound Amtrak train at Alexandria's Union StationAlexandria Union Station, the city's historic train station, is served by both Amtrak intercity and Virginia Railway Express regional rail service. The station is directly adjacent to the King Street – Old Town Washington Metro station, at the convergence of the Blue and Yellow Lines. Three other Metro stations that lie within the city limits are Braddock Road, Van Dorn Street, and Eisenhower Avenue.
The traditional boundary between Old Town and the latterly annexed sections of the city followed the railway now owned by CSX Transportation.
The city government operates its own mass transit system, the DASH bus, connecting points of interest with local transit hubs. Metrobus, Washington Metro, and the Virginia Railway Express, better known as the VRE, also serve Alexandria. The city also offers a free trolley service on King Street from the King Street Metro Station to the Waterfront and a water taxi to and from the National Harbor development in Prince George's County, Maryland.