Maryland Route 66

Maryland Route 66
Maryland Route 66 highlighted in red
Route information
Maintained by MDSHA and Town of Smithsburg
Length	12.84 mi[1] (20.66 km)
Existed	1927–present
Major junctions
South end	US 40 Alt. in Boonsboro
Major intersections	US 40 in Beaver Creek I-70 in Beaver Creek MD 64 in Cavetown
North end	MD 64 near Smithsburg
Location
Country	United States
State	Maryland
Counties	Washington
Highway system
Maryland highway system Interstate US State Scenic Byways
← MD 65 → MD 67

Maryland Route 66 (MD 66) is a state highway in the U.S. state of Maryland. Known for most of its length as Mapleville Road, the state highway runs 12.84 miles (20.66 km) from U.S. Route 40 Alternate (US 40 Alternate) in Boonsboro north to MD 64 near Smithsburg. MD 66 parallels the western flank of South Mountain in eastern Washington County, connecting Boonsboro and Smithsburg with Interstate 70 (I-70) and US 40. MD 66 was constructed in the late 1920s and early 1930s from Boonsboro to Cavetown. The state highway was extended north through Smithsburg after MD 64 bypassed the town in the late 1950s.