New York State Route 234

New York State Route 31
Map of western and central New York with NY 31 highlighted in red
Route information
Maintained by NYSDOT, the cities of Niagara Falls, Lockport, and Rochester and the villages of Medina and Newark
Length:	208.74 mi (335.93 km)
Existed:	mid-1920s – present
Major junctions
West end:	NY 104 in Niagara Falls
	NY 78 in Lockport NY 98 in Albion NY 19 near Brockport NY 390 in Greece I-490 in Rochester NY 21 in Palmyra NY 14 in Lyons NY 690 in Baldwinsville NY 57 in Liverpool I-81 in Cicero NY 13 north of Canastota
East end:	NY 26 in Vernon
Location
Counties:	Niagara, Orleans, Monroe, Wayne, Ontario, Seneca, Cayuga, Onondaga, Madison, Oneida
Highway system
New York Highways Interstate U.S. State Reference Parkways ← NY 30A NY 31A → ← NY 233 NY 235 →

New York State Route 31 (NY 31) is a state highway that extends for 208.74 miles (335.93 km) across western and central New York in the United States. The western terminus of the route is at an intersection with NY 104 in the city of Niagara Falls. Its eastern terminus is at a traffic circle with NY 26 in Vernon Center, a hamlet within the town of Vernon. Over its routing, NY 31 spans 10 counties and indirectly connects three major urban areas in Upstate New York: Buffalo–Niagara Falls, Rochester, and Syracuse. The route is one of the longest routes in New York State, paralleling two similarly lengthy routes, NY 104 to the north and NY 5 to the south, as well as the Erie Canal, as it proceeds east.

Much of NY 31 west of Jordan was originally designated as part of a legislative route from the late 1900s to the early 1920s. NY 31 itself was assigned in the mid-1920s, utilizing all of legislative Route 30 (modern NY 31, NY 429, and NY 104) west of Rochester and much of its current alignment from Rochester to Lenox. At Lenox, NY 31 turned southeast to follow what is now NY 316 and NY 46 to NY 5 in Oneida. It was realigned by 1929 to continue west to Lewiston on Ridge Road and altered in the 1930 renumbering of state highways in New York to continue east to Utica via Verona. With the advent of U.S. Route 104 (US 104) c. 1935, NY 31 was realigned west of Rochester to follow most of its modern routing.