c. 1940; "The Windsor-Detroit Tunnel is one mile long, the bore is 33 ft., roadway 22 ft., head clearance 13 1/2 ft. Regular service of 14 buses make 141 trips daily each way and carry about 11 000 passengers daily. 574 light boxes light the tunnel and 24 fans with capacity of 1,500,000 cubic feet of fresh air per minute furnish ventilation."; centre background: Prince Edward Hotel; centre left: Norton Palmer Hotel.