Pennsylvania Avenue

Pennsylvania Avenue is a diagonal street in Washington, D.C. and Prince George's County, Maryland that connects the White House and the United States Capitol and then crosses the city to Maryland. In Maryland it is also Maryland Route 4 to MD-717 where it becomes Stephanie Roper Highway. The section between the White House and Congress is called "America's Main Street"; it is the location of official parades and processions, as well as protest marches. Moreover, Pennsylvania Avenue is an important commuter road and is part of the National Highway System.
The avenue runs for 5.8 miles inside Washington, but the 1.2 miles of Pennsylvania Avenue from the White House to the United States Capitol building is considered the most important. It continues within the city for 3.5 miles , from the southeast corner of the Capitol grounds through the Capitol Hill neighborhood, and over the Anacostia River on the John Philip Sousa Bridge. Crossing most of Prince George's County, Maryland, it ends 9.5 miles from the DC line at the junction with MD 717 in WUpper Marlboro where the name changes to the Stephanie Roper Highway, for a total length of 15.3 miles . Stephanie Roper Highway used to be Pennsylvania Avenue, but was renamed in 2012. In addition to its street names, in Maryland it is designated as Maryland Route 4. At one point in the mid-20th century, Pennsylvania Avenue was designated DC 4, an extension of Maryland Route 4 that reached at least the east side of the White House.

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