Maryland Route 858 (MD 858) is a collection of unsigned state highways in the U.S. state of Maryland. These four highways are old segments of MD 67 between Rohrersville and Boonsboro in southeastern Washington County. These highways were designated when MD 67 was relocated in the early 1960s. The longest segment is MD 858F, which runs exactly 1 mile (1.6 km) between a pair of intersections with MD 67 in Rohrersville. In addition to the four existing highways, there are several county-maintained segments of old MD 67 between Rohrersville and Boonsboro and at Gapland, Brownsville, and Weverton south of Rohrersville.