U.S. Route 1 in Maryland

U.S. Route 1
US 1 highlighted in red
Route information
Maintained by MDSHA, BCDOT
Length	80.86 mi[1][2] (130.13 km)
Existed	November 11, 1926[3]–present
Tourist routes	Mason and Dixon Scenic Byway Lower Susquehanna Scenic Byway
Major junctions
South end	US 1 at District of Columbia border in Mount Rainier
Major intersections	I-95 / I-495 in College Park MD 200 Toll near Beltsville MD 100 near Elkridge I-895 Toll near Relay I-195 in Relay I-695 near Arbutus US 40 in Baltimore I-83 in Baltimore I-695 near White Marsh US 222 in Conowingo
North end	US 1 at Pennsylvania border near Rising Sun
Location
Country	United States
State	Maryland
Counties	Prince George's, Howard, Baltimore, City of Baltimore, Harford, Cecil
Highway system
United States Numbered Highway System List Special Divided Maryland highway system Interstate US State Scenic Byways
← MD 998 → MD 2

U.S. Route 1 (US 1) is the easternmost and longest of the major north–south routes of the older 1920s era United States Numbered Highway System, running from Key West, Florida, to Fort Kent, Maine. In the U.S. state of Maryland, it runs 81 miles (130 km) from the Washington, D.C. line to the Pennsylvania state line near the town of Rising Sun.

US 1 is paralleled by several major highways as it passes through Maryland, including Interstate 95 (I-95), the Baltimore–Washington Parkway (B–W Parkway), US 29, and US 301. Thus, US 1 has lost its significance as a long distance route through the state. It is often congested, however, because it remains a major route in the individual towns it traverses.