The Baltimore–Washington Parkway is a controlled-access parkway in the U.S. state of Maryland, running southwest from Baltimore to Washington, D.C. The road begins at an interchange with U.S. Route 50 (US 50) near Cheverly in Prince George's County at the Washington, D.C. border, and continues northeast as a parkway maintained by the National Park Service (NPS) to MD 175 near Fort Meade, serving many federal institutions. This portion of the parkway is dedicated to Gladys Noon Spellman, a representative of Maryland's 5th congressional district, and has the unsigned Maryland Route 295 (MD 295) designation. Commercial vehicles, including trucks, are prohibited within this stretch. This section is administered by the NPS's Greenbelt Park unit. After leaving park service boundaries the highway is maintained by the state and signed with the MD 295 designation. This section of the parkway passes near Baltimore–Washington International Thurgood Marshall Airport.

U.S. Route 50 is a major east–west route of the U.S. Highway system, stretching just over 3,000 miles (4,800 km) from West Sacramento, California, east to Ocean City, Maryland, on the Atlantic Ocean. In the U.S. state of Maryland, US 50 exists in two sections. The longer of these serves as a major route connecting Washington, D.C., with Ocean City; the latter is the eastern terminus of the highway. The other section passes through the southern end of Garrett County for less than 10 miles (16 km) as part of the Northwestern Turnpike, entering West Virginia at both ends. One notable section of US 50 is the dual-span Chesapeake Bay Bridge across the Chesapeake Bay, which links the Baltimore–Washington metropolitan area with the Eastern Shore region, allowing motorists to reach Ocean City and the Delaware Beaches.