The surface road layout in Washington, D.C., consists primarily of numbered streets along the north–south axis and lettered streets (followed by streets named in alphabetical order) along the east–west axis. Avenues named for each of the 50 U.S. states crisscross this grid diagonally, and where the avenues intersect, traffic circles often occur. Many circles are named for American Civil War generals and admirals, while several neighborhoods take their names from nearby circles. There are approximately 36 roundabouts currently in the District.
Chevy Chase Circle – intersection of Western and Connecticut Avenues, Chevy Chase and Magnolia Parkways, and Grafton Street; circle is only half within the District; the other half is in Chevy Chase, Maryland
Scott Circle – intersection of Rhode Island and Massachusetts Avenues and 16th Street, with an underpass for 16th Street
Sheridan Circle – intersection of Massachusetts Avenue and R and 23rd Streets
Sherman Circle – intersection of Kansas and Illinois avenues and Crittenden and 7th Streets
Tenley Circle – intersection of Wisconsin and Nebraska Avenues, Fort Drive, and Yuma Street
Thomas Circle – intersection of Massachusetts and Vermont Avenues and 14th and M Streets, with an underpass for Massachusetts Avenue
Ward Circle – intersection of Massachusetts and Nebraska Avenues
Washington Circle – intersection of New Hampshire and Pennsylvania Avenues and K and 23rd Streets, with a K Street underpass
Columbus Circle – intersection of Delaware, Louisiana, and Massachusetts Avenues and E and First Streets; Union Station and its access roads interrupt this circle on one side, making it more of a semicircle. It is also known as Columbus Plaza. Prior to the construction of the Columbus Memorial at its center in 1912, it was called Union Station Plaza.
Dave Thomas Circle - triangular area bounded by Florida Avenue, New York Avenue and First Street Northeast. Though not part of the original city design, traffic patterns mimic other circles.
Truxton Circle – now defunct, existing only as the name of a neighborhood; formerly the intersection of Florida Avenue, North Capitol Street, Q Street NW, and Q Street NE; this circle lay on the border of Northwest and Northeast Washington.