The Baltimore-Washington Parkway was the original freeway connecting Baltimore, Maryland and Washington, DC, replacing U.S. Route 1 and its many traffic lights between the two cities. From its southern terminus at the District of Columbia line - past which it continues as DC Route 295, the Anacostia Freeway - to its interchange with Maryland Route 175 in the Jessup area of Anne Arundel County, it is maintained by the National Park Service, while from there to its northern terminus at Interstate 95 in southwest Baltimore it is maintained by the Maryland Transportation Authority as Maryland Route 295, a designation which continues northward along Russell Street, then the one-way pair of Greene and Paca streets to eastbound US 40, Orleans Street.

Each portion of the Parkway has drastically different visual aesthetics due to being under the responsibility of different authorities. The National Park segment passes through the areas of Cheverly, Bladensburg, Riverdale, Greenbelt and south Laurel in Prince George's County, and Annapolis Junction and Hanover in Anne Arundel County; it has interchanges with the Capital Beltway (I-95/495) and Maryland Route 32, and exits serving the NASA Goddard Space Center, Patuxent Wildlife Refuge, and Fort Meade. As MD 295, the Parkway has an exit near the Arundel Mills Mall and passes to the west of the Baltimore/Washington International Airport, with interchanges at Maryland Route 100 and Interstates 195, 695 (Baltimore Beltway) and 895 (Harbor Tunnel).