Maryland Route 179 is a state highway in the U.S. state of Maryland. Known for most of its length as St. Margarets Road, the highway runs 3.16 miles (5.09 km) from MD 648 near Annapolis east to the end of state maintenance in Cape St. Claire. MD 179 serves a suburban area near the southern end of the Broadneck Peninsula of northeastern Anne Arundel County. The state highway was paved in the 1920s from its western end to Skidmore near Sandy Point. MD 179 was truncated at what is now U.S. Route 50 /US 301 when their predecessor highway replaced the stretch to Skidmore in the early 1940s. MD 179 was extended into Cape St. Claire in the early 1990s.

Maryland Route 180 is a state highway in the U.S. state of Maryland. Known for most of its length as Jefferson Pike, the state highway runs 14.95 miles (24.06 km) from U.S. Route 340 in Knoxville east to Ballenger Creek Pike and Interstate 70 (I-70) in Frederick. MD 180 is the old alignment of US 340 through Knoxville, Petersville, and Jefferson in the Middletown Valley of western Frederick County. The state highway was originally constructed in the early 1910s and designated US 340 in 1927. MD 180 was assigned to the highway bypassed by the US 340 freeway between Sandy Hook in far southern Washington County and Jefferson in the mid-1960s. The state highway was extended east to Frederick and south along Ballenger Creek Pike after the US 340 freeway was completed in the late 1960s. MD 180 was rolled back to Frederick and removed from Washington County in 1989.