Hempstead Turnpike

New York State Route 24 (NY 24) is a east–west state highway on Long Island in the U.S. state of New York. The highway is split into two segments, with the longest and westernmost of the two extending from an interchange with Interstate 295 (I-295, named the Clearview Expressway) and NY 25 (Hillside Avenue) in the Queens Village section of the New York City borough of Queens to an intersection with NY 110 in East Farmingdale in the Suffolk County town of Babylon. The shorter eastern section, located in eastern Suffolk County, extends from an interchange with I-495 in Calverton to an intersection with County Route 80 (CR 80) in Hampton Bays.

NY 24 is one of three highways in New York that are split into two segments; the others are NY 42 in the Catskills and NY 878 in Queens and Nassau County. Like NY 42, NY 24 was a continuous route when it was assigned as part of the 1930 renumbering of state highways in New York. The highway was split into two pieces in the mid-1930s. For a brief period during the late 1950s and early 1960s, NY 24 was routed on the Long Island Expressway from Manhattan to East Hills while its original surface routing was designated New York State Route 24A.

Most of the route is known as Hempstead Turnpike.

Western segment

Queens Village to Nassau Coliseum

NY 24 begins at an intersection with the southern end of I-295 (the Clearview Expressway) and a junction with NY 25 (Hillside Avenue) in the Queens Village section of Queens. NY 24 proceeds southeast along two one-way couplets along Hollis Court Boulevard and 212th Street through dense housing for several blocks (the only unsigned section of the route). At the intersection with 91st Avenue, the couplets bend southward, entering an intersection with Jamaica Avenue, where NY 24 turns off Hollis Court and 212th and follows Jamaica Avenue eastbound for a block. At the junction with Hempstead Avenue, NY 24 turns off Jamaica for Hempstead, crossing under the Long Island Rail Road (LIRR) main line through Queens Village.

Passing a Long Island Rail Road substation, NY 24 proceeds southeast along the four-lane commercial strip of Hempstead Avenue, intersecting with Springfield Boulevard as it crosses through Queens Village. A short distance later, the route enters a partial cloverleaf interchange with the Cross Island Parkway's exit 26B. After crossing the Cross Island Parkway, NY 24 enters Nassau County, changing names to Hempstead Turnpike and passing south of Belmont Park Racetrack and the Belmont Park LIRR station, along with UBS Arena, the home of the New York Islanders of the National Hockey League. Now a six-lane boulevard through the town of Hempstead, NY 24 crosses several parking lots used for Belmont Park Racetrack and UBS Arena, paralleling the grounds to the south for several blocks.

After crossing into the Elmont neighborhood of Hempstead, NY 24 reduces to four lanes, crossing through a long commercial strip east of the racetrack. The route crosses through East Elmont before entering Floral Park Crest, where the roadway bends northeast through Hempstead. After crossing an intersection with Covert and Meacham Avenues, NY 24 straightens eastward once again, crossing a long commercial strip through town. The route soon makes a short bend to the southeast, crossing an intersection with New Hyde Park Road and Franklin Avenue later into West Hempstead. In West Hempstead, NY 24 crosses over the former connection between the Long Island Railroad West Hempstead Branch and Hempstead Branch before entering an intersection with NY 102 (Front Street).

At this intersection, NY 24 drops the Hempstead Turnpike moniker, changing to Fulton Avenue. NY 24 then proceeds northeast through downtown Hempstead, remaining a four-lane commercial street through the city, bending south of a local park. At the junction with Clinton Street, NY 24 bends east for a block, turning northeast again at Peninsula Boulevard. Paralleling NY 102, NY 24 returns to its northeastern progression, regaining the Hempstead Turnpike moniker in front of Hofstra University. At Oak Street on the western end of the campus, NY 24 becomes a four-lane divided highway through Hempstead, passing south of Hofstra University Stadium and past several parking lots for the campus. East of Hofstra Boulevard, the road widens to six lanes. Just after Earle Ovington Boulevard, the route continues east in to Uniondale and runs alongside the parking lots for Nassau Coliseum, the former home of the Islanders from their 1972 founding until 2015, then 2018 until 2021, when they moved west down the pike to UBS Arena.

Nassau Coliseum to Farmingdale

At the junction with Glenn Curtiss Boulevard, NY 24 passes the main entrance to the Coliseum's parking lots before passing north of Rexcorp Plaza. Just after Rexcorp Plaza, NY 24 enters an interchange (exits M4 and M5) with the Meadowbrook State Parkway. After the Meadowbrook, NY 24 enters East Meadow, remaining a six-lane boulevard past Merrick Avenue, passing south of Eisenhower Park. While the park runs along the westbound lanes, several commercial businesses line the eastbound lanes. After Bly Road, the park changes over to more businesses and a short distance later, NY 102 terminates at NY 24 at Front Street. After Carman Avenue, the route passes south of Nassau University Medical Center before returning to the commercial businesses that have surrounded the roadway.

Just to the east of Nassau University Medical Center, NY 24 enters an intersection with NY 106 (North Newbridge Road), and four blocks later, exit W3 of the Wantagh State Parkway. Continuing east through the town of Hempstead, NY 24 remains a six-lane divided boulevard, crossing north of the Levittown Public Library as the route crosses into Levittown, intersecting with Jerusalem Avenue at the western end of the community. NY 24 continues east along a commercial strip into an intersection with North Wantagh Avenue, bending southeast into an intersection with NY 107 (Hicksville Road). The route then crosses into the town of Oyster Bay. Retaining the Hempstead Turnpike name, NY 24 enters the Plainedge neighborhood of Oyster Bay.

After passing St. Joseph's Hospital, NY 24 crosses through Plainedge and into a large cloverleaf interchange (exit 7) with the Seaford–Oyster Bay Expressway (NY 135). Three blocks to the east, NY 24 condenses to four lanes, entering a partial cloverleaf interchange with the Bethpage State Parkway (exit B3). After crossing over the Bethpage, the route proceeds northeast through the town of Oyster Bay, crossing into the town of Farmingdale. After crossing under a line of the Long Island Rail Road, the route crosses Merritt Avenue at-grade, entering a junction with NY 109 (Fulton Street). Past the junction with NY 109, NY 24 changes monikers to Conklin Street, crossing through Farmingdale as a four lane street.

For several blocks, NY 24 passes residential homes, before becoming a two-lane commercial street. A short distance to the east, the route intersects with Secatogue Avenue, which connects to the Farmingdale station to the northwest. Re-expanding to four lanes, NY 24 crosses through Farmingdale on Conklin before crossing the county line into Suffolk County. Now in the town of Babylon, retaining the Conklin Street moniker before entering an at-grade junction with NY 110 (Broad Hollow Road) in front of Airport Plaza. This junction serves as the eastern terminus of NY 24's western segment.

As of October 2014, NY 24's Farmingdale section between its junction with New York State Route 109 and the eastern terminus at New York State Route 110 has been reduced to a two lane street.

Eastern segment

The eastern segment of NY 24 begins at exit 71 of the Long Island Expressway (I-495) in the Calverton section of Brookhaven just east of the former Calverton station. NY 24 proceeds eastward along Edwards Avenue, concurrent with County Route 94 (CR 94) before changing monikers at the corner of South River Road. NY 24 bends northeast along Nugent Drive as a four-lane arterial through Brookhaven. NY 24 and CR 94 cross through Peconic Bog County Park, crossing into the town of Southampton. After leaving Peconic Bog County Park, the routes bend northeast along Nugent, paralleling the Peconic River