Maryland Route 550

Maryland Route 550
Maryland Route 550 highlighted in red
Route information
Maintained by MDSHA
Length	24.43 mi[1] (39.32 km)
Existed	1933–present
Tourist routes	Journey Through Hallowed Ground Byway
Major junctions
South end	MD 26 in Libertytown
Major intersections	MD 194 in Woodsboro MD 77 in Thurmont US 15 in Thurmont MD 491 in Fort Ritchie
North end	Pen Mar Road in Fort Ritchie
Location
Country	United States
State	Maryland
Counties	Frederick, Washington
Highway system
Maryland highway system Interstate US State Scenic Byways
← MD 547 → MD 552

Maryland Route 550 (MD 550) is a state highway in the U.S. state of Maryland. The state highway runs 24.43 miles (39.32 km) from MD 26 in Libertytown north to Pen Mar Road in Fort Ritchie. MD 550 runs southeast–northwest across central Frederick County, connecting Fort Ritchie in the northeastern corner of Washington County and Libertytown with the towns of Thurmont and Woodsboro and the smaller communities of Creagerstown and Sabillasville. South of the highway's junction with U.S. Route 15 (US 15) in Thurmont, the state highway passes through the wide valley of the Monocacy River; to the north, the highway passes along the northern edge of Catoctin Mountain and crests South Mountain near Blue Ridge Summit, Pennsylvania.

MD 550 was built in two main sections. The highway from Thurmont to Blue Ridge Summit was constructed in the mid-1920s as Maryland Route 81 (MD 81). MD 81 was extended west to Fort Ritchie in the mid-1930s. MD 550 was constructed from Libertytown to Woodsboro in the mid to late 1930s. A second disjoint section of the state highway was built from Creagerstown to Thurmont in the late 1930s. The two segments of MD 550 were united when the designation was assigned to the highway between Woodsboro and Creagerstown in the mid-1950s. MD 550 was extended northwest from Thurmont to Fort Ritchie, assuming all of MD 81, in the late 1970s.