 Continuing northwest through Wales, NY 78 remains a two-lane rural street known as Strykersville Road until intersecting with US 20A (Big Tree Road) at a T-intersection. US 20A and NY 78 become concurrent along Big Tree, proceeding west through the town of Wales. The routes remain a two-lane residential street for a distance, intersecting with CR 383 (Reiter Road) as it winds west. Now in the town of Aurora, US 20A and NY 78 enter a large interchange with NY 400 (the Aurora Expressway). A short distance later, the routes enter the village of East Aurora. Now known as Main Street, US 20A and NY 78 proceed west as a two-lane village street, intersecting with NY 16 (Olean Road) and the southern continuation of CR 6 (Pine Street).
