Maryland Route 355 (MD 355) is a 36.75-mile (59.14 km) north–south road in western central Maryland in the United States. The southern terminus of the route, Wisconsin Avenue, is located in the Bethesda CDP, at the Washington, D.C. border. It continues south into Washington, D.C. as Wisconsin Avenue NW. The northern terminus is just north of a bridge over Interstate 70 (I-70)/U.S. Route 40 (US 40) in the city of Frederick in Frederick County, where the road continues north as Market Street through Frederick towards MD 26.