Editing Interstate 99 (section)

===Northern segment===
{{main|U.S. Route 15 in New York}}
[[File:US 15 south at Presho NY exit.jpg|thumb|right|Looking southward along US&nbsp;15 (now I-99) from the Smith Road overpass in Presho prior to the road's completion. The highway previously narrowed from four to two lanes in the background]]
The northern segment of I-99 is entirely concurrent with [[U.S. Route 15 in New York|US&nbsp;15]] and starts at the junction of US 220, US 15, and [[Interstate_180_(Pennsylvania)|I-180]]. I-99 crosses through mountainous terrain in [[Lycoming County, Pennsylvania|Lycoming]] and [[Tioga County, Pennsylvania|Tioga]] counties, bypassing [[Mansfield, Pennsylvania|Mansfield]]. The route crosses the Pennsylvania–[[New York (state)|New York]] border north of [[Lawrenceville, Pennsylvania]]. A four-lane freeway through the [[Steuben County, New York|Steuben County]] town of [[Lindley, New York|Lindley]], I-99 crosses through a rock cut, making a large bend to the north and bypassing the hamlet of [[Presho, New York|Presho]]. The freeway enters a [[partial cloverleaf interchange]] with [[County Route 5 (Steuben County, New York)|County Route&nbsp;5]] (CR&nbsp;5; Smith Road). After CR&nbsp;5, I-99 turns northeast through the town of [[Erwin, New York|Erwin]], running to the west of the Indian Hills Golf Club. Making a gradual bend further to the northeast, the freeway crosses the [[Canisteo River]] and enters the hamlet of Erwins, where it enters a [[diamond interchange]] with [[New York State Route 417]] (NY&nbsp;417; Addison Road). After NY&nbsp;417, it then turns alongside [[Norfolk Southern Railway]]'s [[Southern Tier Line]] (former [[Erie Railroad]] main line). Now paralleling the tracks and NY&nbsp;417, I-99/US&nbsp;15 crosses through Erwin, entering exit&nbsp;11, which connects to NY&nbsp;417 once again, next to Gang Mills Yard,<ref name="bing">{{bing maps|url=http://binged.it/Qzs6yW|title=overview map of Interstate 99 in New York|access-date=July 24, 2012}}</ref> the site of former [[Painted Post station]].<ref name="yanosey">{{cite book|last=Yanosey|first=Robert J.|others= Lawton, Devon (photographer)|title=New York|publisher=Morning Sun Books|location=Scotch Plains, New Jersey|date=2006|series=Erie Railroad Facilities in Color|volume=2: NY|page=71|isbn=1-58248-196-2}}</ref>

[[File:Interstate 99 entering New York.jpg|thumb|left|I-99/US&nbsp;15 entering New York]]
After Gang Mills Yard, I-99 crosses through the [[Gang Mills, New York|Gang Mills]] section of Erwin, entering a large interchange at the northern end of the neighborhood. Signed exit&nbsp;12, this interchange serves [[County Route 107 (Steuben County, New York)|CR&nbsp;107]] (Robert Dann Drive) via NY&nbsp;417. After CR&nbsp;107, I-99 enters a large interchange that utilizes several flyover ramps between I-99, US&nbsp;15, [[Interstate 86 in New York|I-86]], and [[New York State Route 17|NY&nbsp;17]] ([[Southern Tier Expressway]]). Ramps are also present, connecting to [[New York State Route 352|NY&nbsp;352]]. This interchange serves as the northern terminus of both I-99 and US&nbsp;15.<ref name="bing" />