High Quality Content by WIKIPEDIA articles! Maryland Route 231 (MD 231) is a state highway in the U.S. state of Maryland. The state highway runs 16.39 miles (26.38 km) from Olivers Shop Road near Hughesville east to MD 765 in Prince Frederick. MD 231 crosses the Patuxent River on the Benedict Bridge, which connects Benedict in eastern Charles County with Hallowing Point in central Calvert County. Due to the state highway serving as the sole connection between the two areas of Southern Maryland, MD 231 is part of the National Highway System between MD 5 in Hughesville and MD 2 and MD 4 in Prince Frederick.