New York State Route 110 (NY 110) is a major north–south state highway along the western border of Suffolk County, New York. It runs between the village of Amityville in the town of Babylon and Halesite in the town of Huntington. NY 110 comes close to the Nassau County line several times in the town of Babylon, which is only surpassed by NY 108 in distance to the county line for a state highway.
Route description
NY 110 begins at an intersection with NY 27A (Merrick Road) in the Suffolk County village of Amityville. Proceeding northward as Broadway, NY 110 crosses through downtown Amityville as a two-lane village street. Expanding to four lanes, the route intersects at-grade with County Route 12 (CR 12; Oak Street) before crossing under the Montauk Branch of the Long Island Rail Road, a block east of Amityville station. NY 110 continues north along Broadway, forking northwest at a junction with Albany Avenue. Passing Brunswick Hospital, the route intersects with the western terminus of CR 2 (Dixon Street) before entering a cloverleaf interchange with NY 27 (Sunrise Highway).
NY 110 continues into North Amityville, becoming a four-lane boulevard through the center of the hamlet. The route crosses through several commercial districts in North Amityville, proceeding northwest towards the Nassau County line. Bending northward alongside the county line, NY 110 enters an interchange with the Southern State Parkway (exit 32S–N), where the route becomes an expressway and changes names to Broadhollow Road. NY 110 then expands to six lanes, intersecting with CR 47 (Main Street / Great Neck Road). Bending northeast and away from the county line, NY 110 continues as a six-lane expressway, crossing through the town of Babylon into East Farmingdale.
Entering East Farmingdale, NY 110 crosses over the Central Branch of the Long Island Rail Road and enters a large grade-separated interchange with NY 109 (Farmingdale Road) just west of Republic Airport. NY 110 continues north through Babylon as a six-lane expressway past the runway of Republic Airport, passing a small campus of Molloy University. Entering Airport Plaza, the route continues north into an intersection with the eastern terminus of the western segment of NY 24 (Conklin Street). NY 110 continues north along Broad Hollow Road, going underneath the LIRR Main Line at the site of its former Republic station, then passing the campus of State University of New York at Farmingdale. Just north of the campus, the route leaves the town of Babylon, crossing into the town of Huntington.
Now in Huntington, NY 110 crosses into East Melville, passing through several commercial strips, entering exit 49S–N of the Long Island Expressway (I-495), a cloverleaf interchange. After the Long Island Expressway, NY 110 reduces from six lanes to four, intersecting with CR 3 (Pinelawn Road). The route crosses several streets in at-grade junctions, crossing Old Country Road before changing names to Walt Whitman Road. After the name change, NY 110 crosses into an interchange with the Northern State Parkway (exit 40) and becomes a four-lane boulevard. Continuing north along Walt Whitman Road, NY 110 proceeds north through a commercial strip in Melville. The route proceeds north as a four-lane boulevard for several miles, crossing West Hills County Park and past Walt Whitman Shops. Just north of Walt Whitman Shops, NY 110 enters an at-grade intersection with NY 25 (West Jericho Turnpike) in the hamlet of South Huntington.
North of NY 25, NY 110 shrinks to a two-lane road, crossing through South Huntington as Walt Whitman Road until the junction with New York Avenue, where that name terminates. NY 110 then proceeds northwest along New York Avenue, crossing through Huntington Station through a long commercial strip. Crossing through the village, NY 110 intersects with CR 11 (Pulaski Road). Passing the Huntington Public Library, NY 110 crosses under the Port Jefferson Branch of the Long Island Railroad and the Huntington station. Expanding back to four lanes, the route continues through Huntington, bending northwest at Henry Street. NY 110 crosses northwest, passing a large shopping center.