Louisiana Highway 21

Louisiana Highway 21
Route information
Maintained by Louisiana DOTD
Length	52.1 mi[1] (83.8 km)
Existed	1955 renumbering–present
Major junctions
South end	LA 22 / LA 1077 in Madisonville
Major intersections	I-12 near Covington US 190 in Covington LA 36 in Covington LA 59 near Waldheim LA 40 near Bush LA 41 in Bush LA 16 in Sun LA 10 in Bogalusa
North end	MS 35 at Mississippi state line
Location
Country	United States
State	Louisiana
Highway system
Louisiana State Highway System Interstate US State Scenic
← LA 20 → LA 22

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.