Louisiana Highway 21 (LA 21) is a state highway in Louisiana that serves St. Tammany and Washington Parishes. It spans 51.76 miles (83.30 km) and is signed north and south.
Louisiana Highway 21 (LA 21) is a state highway in Louisiana that serves St. Tammany and Washington Parishes. It spans 51.76 miles (83.30 km) and is signed north and south. (en)