South Oyster Bay in the context of "Great South Bay"

The Outer Barrier, also known as the Long Island and New York City barrier islands, refers to the string of barrier islands that divide the lagoons south of Long Island, New York from the Atlantic Ocean. These islands include Long Beach Barrier Island, Barnum Island, Jones Beach Island, Fire Island and Westhampton Island. The outer barrier extends 75 miles (121 km) along the South Shore of Long Island, from the Rockaway Peninsula in New York City to the east end of Shinnecock Bay in Suffolk County.

The lagoons enclosed by the barrier islands are Jamaica Bay, Brosewere Bay, Hewlett Bay, Reynolds Channel, Middle Bay, East Bay, South Oyster Bay, Great South Bay, and arms of the Great South Bay that have their own geographic names: Great Cove, Nicoll Bay, Patchogue Bay, Bellport Bay, Narrow Bay, Moriches Bay, Quantuck Bay, Tiana Bay, and Shinnecock Bay. East Rockaway Inlet, Jones Inlet, Fire Island Inlet, Old Inlet, Moriches Inlet, and Shinnecock Inlet pierce the barrier, forming the individual sandy islands. The resort communities of Atlantic Beach, Long Beach, and Westhampton Beach; the Fire Island National Seashore, Robert Moses State Park, Jones Beach State Park, and other recreational areas are found there. The low-lying islands are subject to wave erosion, and, during storms, they are sometimes inundated and cut through.

Jones Inlet is located at the westernmost end of the 17-mile (27 km) long Jones Beach barrier island that runs along Long Island's south shore. The inlet separates Jones Beach State Park's West End from the community of Point Lookout and connects South Oyster Bay with the Atlantic Ocean. In 2006, the inlet handled approximately 10,000 tons of commercial tonnage.

Shifting sand bars and shallow waters have made the inlet treacherous for boaters to navigate, which prompted New York State to allocate $7.6 million of funding for the United States Army Corps of Engineers to dredge the inlet in 2008. In addition to improving navigational safety for vessels, the sand dredged from the inlet was pumped onto the Point Lookout shoreline to help mitigate the effects of beach erosion. The inlet was previously dredged in 1995-1996. It was also dredged in 2014 and 2022.

The Meadowbrook State Parkway (also known as the Meadowbrook, the Meadowbrook Parkway, Meadowbrook Causeway, or the MSP) is a 12.52-mile (20.15 km) controlled-access parkway in Nassau County, New York, in the United States. Its southern terminus is at a full cloverleaf interchange with the Bay and Ocean parkways in Jones Beach State Park. The parkway heads north, crossing South Oyster Bay and intersecting Loop Parkway before crossing onto the mainland and connecting to the Southern State Parkway in North Merrick. It continues north to the hamlet of Carle Place, where the Meadowbrook Parkway ends at exit 31A of the Northern State Parkway. The Meadowbrook Parkway is designated New York State Route 908E (NY 908E), an unsigned reference route. Most of the road is limited to non-commercial traffic, like most parkways in the state of New York; however, the portion south of Merrick Road is open to commercial traffic.

The Meadowbrook State Parkway was first envisioned in 1924 as part of the Long Island State Park Commission (LISPC) and Robert Moses's system to connect several parks in Nassau and Suffolk counties. One park included in the proposal was Jones Beach State Park, which opened along with the Ocean Parkway in 1929. Construction of the Meadowbrook and Loop causeways began in July 1933, and was slated for completion in January 1935. The Reconstruction Finance Corporation loaned $5,050,000 toward the project, which was completed in October 1934. Nassau County acquired the right-of-way for an extension to the Northern State Parkway in 1936, and the highway was originally intended to be finished for the 1939 World's Fair in Flushing Meadows, Queens. The start of construction was ultimately delayed until December 1953, and the $10 million (1953 USD) highway was completed in October 1956.