The Windsor Subdivision is a rail line owned and operated by the Canadian Pacific Railway (CP) in the Canadian province of Ontario and the U.S. state of Michigan. The line runs from London, Ontario, where the Galt Subdivision continues east, west to Detroit, Michigan. The Windsor Subdivision intersects the Canadian National Railway's at College Avenue in Windsor. The Windsor Subdivision crosses the Canada–United States border through the Detroit River Tunnel and ends at 24th Street in Detroit at Conrail's .