Question: Where in New York is the highway that ends at the toll barrier for Heckscher State Park in Great River?

Context articles: Sunken Meadow State Parkway
New York State Route 332
Great River, New York
Southern State Parkway
Great River Bluffs State Park
Iowa Highway 340
Heckscher State Park
Heckscher State Parkway
Sagtikos State Parkway
New York State Route 27

The Sunken Meadow State Parkway (also known as the Sunken Meadow) is a 6.19 mi long parkway in Suffolk County, Long Island, New York.
 Located entirely within the town of Smithtown, the parkway begins at a cloverleaf interchange with the Northern State Parkway (exits 44–45) and the northern terminus of the Sagtikos State Parkway.
 The parkway, which continues north, is a northern spur of the Sagtikos, which opened in September 1952.
 The northern end of the parkway is at the toll barrier in exit SM5 in the Kings Park section of Smithtown.
 From there, the road continues north through Sunken Meadow State Park to a roundabout at the Long Island Sound.
 The parkway comprises the northern half of New York State Route 908K (NY 908K, an unsigned reference route), with the Sagtikos State Parkway forming the southern portion.
 Commercial vehicles are, like on most parkways, prohibited from using the Sunken Meadow, except for a portion north of NY 25A in Kings Park.
New York State Route 332 (NY 332) is a north–south state highway that extends for 9.05 mi through Ontario County in the Finger Lakes region of New York in the United States.
 The southern terminus of the route is at an intersection with U.S. Route 20 (US 20), NY 5, and NY 21 just south of downtown Canandaigua.
 Its northern terminus is located at the toll barrier preceding New York State Thruway (Interstate 90 or I-90) exit 44 in Farmington.
 NY 332 is the primary route for travelers destined for Canandaigua from locales such as Rochester and Victor to the northwest of the city.
Great River, New York is a suburban hamlet and CDP in the Town of Islip, Suffolk, USA situated approximately 50 mi (55 mi driving) east of NYC on South Shore of L.I., adjoining the Great South Bay, protected from the Atlantic Ocean by Fire Island.
The Southern State Parkway (also known as the Southern State or Southern Parkway) is a 25.53 mi limited-access highway on Long Island, New York, in the United States.
 The parkway begins at an interchange with the Belt and Cross Island parkways in Elmont, in Nassau County, and travels east to an interchange with the Sagtikos State Parkway in West Islip, Suffolk County, where it becomes the Heckscher State Parkway.
 The Southern State Parkway comprises the western portion of unsigned New York State Route 908M (NY 908M), with the Heckscher Parkway occupying the eastern section.
Great River Bluffs State Park is a state park of Minnesota, United States, on the Mississippi River southeast of Winona.
 Originally known as O. L. Kipp State Park, it was renamed in the late 1990s to describe better its resources.
 The park preserves steep-sided bluffs rising 500 ft above the river and the narrow valleys between them, which support rare and fragile plant communities.
 Two of the bluffs have received further protection under the Minnesota Scientific and Natural Areas program, which are known as King's and Queen's Bluff Scientific and Natural Area.
Iowa Highway 340 (Iowa 340) connected U.S. Highway 18 Business (US 18 Bus.)
 in McGregor to Pikes Peak State Park.
 It was designated in 1936 to connect Pikes Peak State Park to the primary highway system, which it did until it was turned over to Clayton County in 2003.
 It was turned over along with 700 miles of other short highways that primarily served local traffic.
 It was mostly replaced by County Road X56.
 Aside from a short connector to the state park gate, the route was a part of the Great River Road.
Heckscher State Park is a 1657 acre state park on the shore of the Great South Bay at East Islip in Suffolk County, New York, USA.
The Heckscher State Parkway (formerly known as the Heckscher Spur) is an 8.24 mi parkway on Long Island, New York, in the United States.
 The parkway, located entirely within the Suffolk County town of Islip, begins at the south end of the Sagtikos State Parkway in West Islip, from where it continues west as the Southern State Parkway.
 It proceeds east as a six-lane parkway through Brentwood and Central Islip, loosely paralleling New York State Route 27 (NY 27).
 At Islip Terrace, the Heckscher Parkway turns southward, crossing NY 27 before ending at the toll barrier for Heckscher State Park in Great River.
 The parkway comprises the eastern portion of New York State Route 908M (NY 908M), an unsigned reference route, with the Southern State Parkway occupying the western section.
 In order to avoid confusion, the highway is signed as an extension of the Southern State Parkway west of the NY 27 interchange (exit 44).
The Sagtikos State Parkway, also known as the Sagtikos or Sagtikos Parkway, known colloquially as "the Sag" is a 5.14 mi north–south limited-access parkway in Suffolk County on Long Island, New York, in the United States.
 It begins at an interchange with the Southern and Heckscher state parkways in the hamlet of West Islip and goes north to a large cloverleaf interchange with the Northern State Parkway in the town of Smithtown, where the Sagtikos ends and the road becomes the Sunken Meadow State Parkway.
 The parkway comprises the southern half of New York State Route 908K (NY 908K), an unsigned reference route, with the Sunken Meadow State Parkway forming the northern portion.
 Commercial vehicles are prohibited from using the Sagtikos State Parkway, a restriction that applies to most parkways in the state.
New York State Route 27 (NY 27) is an east–west 120.58 mi long state highway extending from Interstate 278 (I-278) in the New York City borough of Brooklyn to Montauk Point State Park on Long Island, New York, in the United States.
 Its two most prominent components are Sunrise Highway and Montauk Highway, the latter of which includes the Montauk Point State Parkway.
 East of the interchange with the Heckscher State Parkway in Islip Terrace, NY 27 acts as the primary east–west highway on southern Long Island.
 The entire route in Suffolk, Nassau, and Queens counties was designated by the New York State Senate as the POW/MIA Memorial Highway.
 Every town on the South Shore is accessible through Sunrise Highway.
 The service roads that parallel the highway from Farmingdale to Brookhaven are officially designated, but not signed, as New York State Route 906C and New York State Route 906D.