 U.S. Route 206 followed the route from Trenton to Princeton until 1953, when the southern terminus of Route 27 was cut back to Princeton to avoid the concurrency with U.S. Route 206.Route 27 begins at a traffic light with U.S. Route 206 and County Route 533 in downtown Princeton, Mercer County.The route heads northeast along Nassau Street, the main street of Princeton that runs along the northern edge of Princeton University and is lined with numerous shops and restaurants.