After making a bend to the northeast, the route junctions with the eastern terminus of CR 256, where NY 157 turns eastward through Berne. Making a large bend to the southeast, NY 157 crosses into John Boyd Thacher State Park, passing multiple entrances and parking lots into various park attractions. Through the park, NY 157 makes various directional changes, but maintains a generally southeast progression, crossing into the town of New Scotland within the park grounds. After leaving the park, the route retains the Thacher Park Road moniker, winding southeast through dense wilderness of New Scotland. Turning to the south, NY 157 junctions with the terminus of CR 311 (Beaver Dam Road). After one more bend to the east, the route intersects with NY 85 (New Scotland Road). This junction, located in the hamlet of New Salem, serves as the eastern terminus of NY 157.