from the WNYP and forming a concurrency with NY 36 north along a four-lane divided highway known as the Maple City Bypass. The overlap ends north of the city limits in the town of Hornellsville, where NY 21 splits from NY 36 and resumes its northeasterly track. Not far to the north of this point is exit 34 of the Southern Tier Expressway, accessed by way of NY 36. From Hornell, NY 21 heads northeast through progressively less developed areas as it winds its way across the hilly terrain of the Southern Tier. For the next , NY 21 serves only small, roadside hamlets, such as Fremont, Haskinville, and Loon Lake. North of Haskinville, NY 21 takes on a more northerly course through the county that eventually brings it to the village of Wayland, where it intersects I-390 at exit 3 south of the village. The interchange also serves as the southern terminus of NY 15 and is adjacent to the north end of NY 415, which terminates north of the exit at NY 21. NY 15 joins NY 21 north into the center of Wayland, where the two routes separate upon intersecting NY 63. While NY 15 continues north from the village into Livingston County, NY 21 leaves Wayland on an east–west alignment, roughly paralleling the northern county line and a B&H Rail Corporation line as it runs through a valley surrounding the Cohocton River. After , the road enters the hamlet of North Cohocton, centered around NY 21's junction with the northern terminus of NY 371. While the river, its valley, and the rail line proceed south from North Cohocton, NY 21 turns to the northeast, ascending out of the valley and finally crossing the county line, at this point bordering Ontario County. The route meanders across another area of hilly, undeveloped terrain to the village of Naples, home to the north end of NY 53 and the south end of NY 245. NY 21 meets the two routes at opposite ends of the community, with NY 53 terminating south of the village center and NY 245 beginning to its north. Naples also serves as NY 21's entrance to the Finger Lakes region; the village itself is located in the southernmost part of the Canandaigua Lake valley. Naples to Williamson NY 21 continues north from Naples, running alongside the western edge of the lake valley, and eventually the