Maryland Route 506 (MD 506) is a state highway in the U.S. state of Maryland. Known as Sixes Road, the state highway runs 3.79 miles (6.10 km) from MD 508 in Bowens east to MD 2/MD 4 near Port Republic. MD 506 provides access to Battle Creek Cypress Swamp. The state highway was constructed from MD 2 to the swamp in the early 1930s and extended to Bowens in the late 1950s.