List of numbered highways in Washington, DC

District of Columbia Routes are numbered highways maintained by District of Columbia's District Department of Transportation (DDOT). In addition to these routes, there are several Interstate and United States Numbered Highways that pass through Washington, D.C. The metro area is also served by three unnumbered, federally maintained, parkways: the Clara Barton Parkway, the Rock Creek and Potomac Parkway, and the George Washington Memorial Parkway (the latter on the west side of the Potomac River, but a portion of it is east of the Boundary Channel).