Highway 401, aka the MacDonald-Cartier Freeway, but commonly referred to as simply "four-oh-one" is the busiest road in North America. 420,000 vehicles drive on it each day. When I walked across one of its local overpasses late tonight it wasn't very busy, but this 15-second shot caught a few traffic trails, anyway!
This view of 401 was taken from the Fountain Street overpass in Cambridge, Ontario. The camera is looking east (towards Toronto, which is about 90-100 km down the road).
