The name "M Street" refers to two major roads in the United States capital of Washington, D.C. Because of the Cartesian coordinate system used to name streets in Washington, the name "M Street" can be used to refer to any east-west street located twelve blocks north or south of the dome of the United States Capitol (not thirteen blocks, as there is no J Street). Thus, in all four quadrants of the city there are streets called "M Street", which are disambiguated by quadrant designations, namely, M Street NW, NE, SW, and SE. M Street NW In Northwest Washington, M Street is a major street downtown and the main east-west street in the Georgetown neighborhood. M Street NW begins at the Key Bridge, which crosses the Potomac River at the 3500 block. To the west of 36th Street, M Street turns into Canal Road. M Street was originally called Bridge Street until the roads in Georgetown were renamed in 1895 to conform to the street names used in Pierre Charles L'Enfant's original plan for the federal city. Where 32nd Street would otherwise be, M Street intersects with Wisconsin Avenue. At 29th Street, it meets the western terminus of Pennsylvania Avenue. This is the last major intersection before the M Street Bridge over Rock Creek, which forms the eastern border of Georgetown. The section in Georgetown carries heavy commuter traffic because it connects Pennsylvania Avenue with the Key Bridge and Canal Road. From Pennsylvania Avenue to Thomas Circle at 14th Street, M Street is designated for one-way traffic with vehicles driving westbound-only. M Street once again becomes two-way in Georgetown. This stretch is highly developed, consisting mainly of apartments from 26th to 21st and businesses from 21st to Thomas Circle. From 14th Street to 5th Street NW, M Street is again two-way. Although, halfway through the 900 block, the street turns eastbound. Between 9th and 7th Streets NW, it passes underneath the Walter E. Washington Convention Center. From 5th Street to North Capitol Street, it assumes a complex traffic pattern because of the intersections and near-intersections of several high-traffic streets: M, New York Avenue/U.S. Route 50, the northern terminus of Interstate 395, New Jersey Avenue, and North Capitol Street. Traffic is west-to-east from 5th to 4th, east-to-west from New York to 4th, and west-to-east from New York through North Capitol and onto M Street NE. M Street NE M Street NE