Mackinac Bridge
Opened to traffic on 11/1/1957, the Mackinac Bridge is the longest suspension span in the world at 8,614 feet. By comparison, the Golden Gate Bridge is 6,450'. The main towers are 552 feet above the Straits of Mackinac. If the wires used to make the support cables were laid end to end, they would circle the earth 1.7 times.