North of Arkport, the Canisteo River makes a turn to the west while NY 36 continues to the northeast, running along the eastern edge of both a marshy area and an extension of the Canisteo River valley. In the town of Dansville, NY 36 intersects the current eastern terminus of NY 70 at an intersection located north of Arkport and due east of Canaseraga. From here northward, the highway takes on a more northeasterly routing as it crosses the northwest corner of the county, where it runs along the west side of Stony Brook State Park and briefly enters the park before emerging from the area just south of the Livingston County line. Across the county line, NY 36 enters the town of North Dansville and the village of Dansville located within. At the southern village line, NY 36 meets the southbound entrance and exit ramps for I-390 at exit 4 and gains the name Clara Barton Street. Due to the angle at which I-390 crosses NY 36 here, the northbound entrance and exit ramps are located another to the north. The route follows Clara Barton Street north into the village center, where it gradually curves northeastward ahead of a junction with Main Street (NY 63) in Dansville's business district. NY 36 turns northwest here, following NY 63 along Main Street for two blocks before returning west on Ossian Street. The highway turns again just six blocks later to follow Dock and Franklin streets northwest toward Dansville Municipal Airport. Ossian Street, meanwhile, continues west as NY 436, which passes under I-390 a short distance to the west. Between NY 436 and I-390 exit 6 near Groveland, NY 36 closely parallels I-390, remaining within or less of it for the entire distance. Just outside Dansville in the shadow of Dansville Municipal Airport, NY 36 connects to I-390 a second time by way of McWhorter Road and exit 5. Outside of Dansville, the highway heads northwestward across gradually less developed areas as it traverses the west side of a wide, flat valley known locally as the flats. After , it intersects the western terminus of NY 258 (named Flats Road) at an intersection situated west of the hamlet of Groveland on the West Sparta–Groveland town line. Not far to the northwest is I-390 exit 6, the third and final meeting between I-390 and NY 36.