Bridge Week!: Mackinac Bridge – Suspension Bridge

Photo Credit: Karl Jansen

Pictured here is the Mackinaw Bridge, which connects the Upper Peninsula of Michigan to the Lower Peninsula. This suspension bridge was finished in 1957, boasting a length of 26,372 feet (4.99 miles) and a longest span of 3,800 feet. Suspension bridges are unique in the way the loads of the bridge are transferred to the ground. The cables of a suspension bridge work in tension, carrying the loads to the two towers which work in compression against the foundations on the earth. The cable ends are then secured in massive blocks of concrete that hold the tension in the cables completing the load path.