 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[1] (335.93 km) | |||
| Existed | mid-1920s[2][3]–present | |||
| Major junctions | ||||
| West end |  NY 104 in Niagara Falls | |||
| East end |  NY 26 in Vernon | |||
| Location | ||||
| Country | United States | |||
| State | New York | |||
| Counties | Niagara, Orleans, Monroe, Wayne, Ontario, Seneca, Cayuga, Onondaga, Madison, Oneida | |||
| Highway system | ||||
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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.
NY 31 was truncated westward to NY 365 in Verona in the early 1940s, moving the eastern terminus of NY 31 to the same junction that also had served as the northern terminus of New York State Route 234, a north–south route that extended southeastward to Vernon Center, since the early 1930s. The two routes continued to share a terminus until 1981, when ownership and maintenance of part of NY 234 was transferred from the state of New York to Oneida County as part of a highway maintenance swap between the two levels of government. In return, the state acquired a pair of county roads that followed a routing parallel to that of the transferred section of NY 234. The new state highways and the remainder of NY 234 became an extension of NY 31.