The Southern State Parkway (also known as the Southern State or the Southern Parkway) is a long east-west limited-access highway on Long Island in the U.S. state of New York. The western terminus of the parkway is at an interchange with the Belt and Cross Island Parkways in Hempstead adjacent to the New York City line. The eastern terminus is at the Heckscher State Parkway in West Islip. The Southern State Parkway comprises the western portion of New York State Reference Route 908M (an unsigned reference route assigned by NYSDOT), with the Heckscher occupying the eastern section. As its name implies, the Parkway services communities along the southern half of the island.
Troop L of the New York State Police, based at Republic Airport in East Farmingdale patrol all of Long Island's parkways.
The directional counterpart to the Southern, the Northern State Parkway, runs roughly parallel to the Southern approximately 7 miles to the north. Both of these roads, along with other parkways in New York State, prohibit trucks and other large commercial vehicles.
