Ocean Parkway is a boulevard in the New York City borough of Brooklyn. Designed by Frederick Law Olmsted and Calvert Vaux, it was built between 1874 and 1876. Ocean Parkway runs roughly 5.5 miles (8.9 km) north to south from the intersection with Prospect Park (Machate) Circle, at the southwestern corner of Prospect Park, to the Atlantic Ocean waterfront at Brighton Beach. The 4.86-mile-long (7.82 km) section between Church Avenue and the Atlantic Ocean is maintained by the New York State Department of Transportation (NYSDOT) as New York State Route 908H (NY 908H), an unsigned reference route.

In general, Ocean Parkway is 210 feet (64 m) wide and consists of a main roadway, two landscaped medians, and two service roads flanking the main road. The western median contains the United States' first bike lane, which opened in 1894, while the eastern side of the parkway contained a bridle path until the 1970s. Commercial vehicles are prohibited from Ocean Parkway, and there is limited public transit. Much of the original parkway remains intact, but the section north of Church Avenue was mostly replaced with the Prospect Expressway in the 1950s; the service roads continue to Park Circle, the original northern terminus. The section south of Church Avenue is a New York City scenic landmark and on the National Register of Historic Places.

Olmsted and Vaux designed Ocean Parkway, along with Eastern Parkway, in the 1860s to connect Prospect Park with neighborhoods further afield. The section north of Kings Highway was constructed from 1873 to 1874, while the section south of Kings Highway was constructed in 1876. Over the years, a variety of building styles including single-family homes, mansions, and apartment buildings were developed along the parkway. Ocean Parkway was originally a dirt road but has been modified several times over the years. The boulevard first received a macadam pavement in the 1920s and was renovated in the 1970s. Ocean Parkway was one of Brooklyn's most dangerous roads by the 21st century.

Ocean Parkway is a boulevard within the New York City borough of Brooklyn, which is coextensive with Kings County in western Long Island, New York. It runs 5.5 miles (8.9 km) from Prospect Park in the north to Brighton Beach and Coney Island in the south. Though Ocean Parkway is almost entirely a surface street, the New York State Department of Transportation (NYSDOT) maintains the segment south of Church Avenue as a state highway and oversees the design of the parkway's intersections. The New York City Department of Transportation (NYCDOT) is responsible for the maintenance of traffic lights and crosswalks there. The NYSDOT designates the 4.86-mile (7.82 km) section south of Church Avenue as an unsigned reference route, New York State Route 908H (NY 908H).

Ocean Parkway begins at Prospect Park (Machate) Circle at the southwestern entrance of Prospect Park, where it intersects with Coney Island Avenue and Fort Hamilton Parkway. At Park Circle, the parkway is divided into four roadways. The outermost roadways are service roads; the inner westbound roadway carries traffic to Ocean Parkway and Fort Hamilton Parkway, and the inner eastbound roadway carries traffic from the Prospect Expressway (New York State Route 27). Ocean Parkway travels west for about 1,000 feet (300 m) before curving southward. There is a pedestrian overpass over the parkway at Sherman Street, just east of this curve. West of the overpass, ramps from Ocean Parkway merge into the Prospect Expressway, which runs in a trench. Due to the presence of the expressway, the western or southbound service road is split into two sections between Prospect Avenue and Fort Hamilton Parkway, while the eastern or northbound service road remains intact.

At Church Avenue, a streetcar tunnel crossed under Ocean Parkway from the 1890s to the 1950s. After Prospect Expressway ends at Church Avenue, Ocean Parkway passes through the neighborhoods of Windsor Terrace, Kensington, Midwood, Homecrest, and Sheepshead Bay. The parkway crosses over the Long Island Rail Road's Bay Ridge Branch in Midwood, and it passes underneath the Belt Parkway in Sheepshead Bay. It runs parallel to Ocean Avenue for much of its route. Ocean Parkway ends at Surf Avenue in Brighton Beach, close to the Riegelmann Boardwalk and Atlantic Ocean. Near its southern end, the parkway divides Brighton Beach to the east and Coney Island to the west.

The landscape firm of Frederick Law Olmsted and Calvert Vaux designed the parkway, while John Y. Culyer was the chief engineer. Olmsted's landscape design firm, the Olmsted Brothers, regarded Ocean Parkway as a "formal pleasure drive" and thus a boulevard; this contrasted with parkways, which the firm defined as "informal pleasure drives". A New York Times article from 1980 characterized Ocean Parkway as "New York City's closest equivalent to a strictly residential boulevard in the European style". According to the historian Elizabeth Macdonald, Ocean Parkway was intended to be a recreational space, as opposed to traditional spaces, which were meant for reflection.

The parkway is similar to Eastern Parkway in its layout. It includes a 70-foot-wide (21 m) central roadway, two 20-foot-wide (6.1 m) grassy medians on each side with bike and pedestrian paths, two 25-foot-wide (7.6 m) service roads on the periphery, and two 15-foot-wide (4.6 m) exterior sidewalks, for a total width of 210 feet (64 m). As designed, there were six rows of trees: two on each median and one on each outer sidewalk. The Brooklyn Parks Commission initially controlled another 30 feet (9.1 m) outside either outer sidewalk, and all buildings on either side of the parkway had to be recessed 30 feet from the sidewalk. The neighborhood's zoning still requires that buildings have a 30-foot-deep lawn.