NY 17 just east of Binghamton is also designated as I-86, creating a temporary gap in the designation. The Broome County segment runs from I-81 at exit 75 in Kirkwood to NY 79 at exit 79 in Windsor. History Origins and the Quickway The first long-distance route through the modern I-86 corridor was NY 17, which extended from Westfield to New Jersey via Harriman when it was assigned in 1924. Much of NY 17 followed a routing parallel or identical to that of the modern Southern Tier Expressway and Quickway; however, it followed a more northerly routing between Westfield and Bemus Point (via modern NY 394 and NY 430) and a more southerly track from Belvidere to Corning (via what is now NY 19 and NY 417). NY 17 was realigned as part of the 1930 state highway renumbering to travel directly from Olean to Wellsville on modern NY 417, located well to the south of today's Southern Tier Expressway. By the late 1940s, the portion of NY 17 through the Catskill Mountains and Orange and Rockland counties had become prone to massive traffic jams due to both its winding and narrow composition and congestion in the villages and hamlets along the highway. As a result, the state of New York began making plans to construct an expressway leading from the New York State Thruway at Harriman to the Catskills. Construction of the NY 17 freeway began in 1947 in the Hudson Valley town of Wallkill. The first section of the new freeway, a bypass of Middletown between Fair Oaks (exit 118A, since removed) and Goshen (exit 123), opened to traffic in July 1951 as a realignment of NY 17. In 1954, several severe accidents occurred along parts of the surface NY 17, compelling the state to make constructing the freeway, dubbed the "Quickway", a higher priority. The road was extended east first, reaching Chester (exit 127) in October 1954 and the Thruway near Harriman in August 1955. To the west, a section of the highway through Sullivan and Delaware counties was built over the right-of-way of the defunct New York, Ontario and Western Railway. Most of the Sullivan County section of the Quickway was completed during the 1950s, with the first section within the county—between Rock Hill (exit 108) and Wurtsboro (exit 114)—opening in December 1956. A second section, from Ferndale (exit 101) to north of Liberty (exit 98),