Highway 401 (Ontario): Termini at Windsor and Cornwall

King's Highway 401 (the 401) is a major east–west freeway across Southern Ontario.

• Western Terminus: Windsor, at the Detroit–Windsor border crossing (connects to I-75 in Michigan).
• Eastern Terminus: Cornwall, at the Quebec border (continues as Autoroute 20 toward Montreal).

At 828 km (514 mi), it is one of the world's busiest highways and the backbone of Ontario's transportation corridor.