The Mackinac Bridge (pronounced /ˈmækɨnɔː/, approximately mack-in-awe), is a suspension bridge spanning the Straits of Mackinac to connect the non-contiguous Upper and Lower peninsulas of the U.S. state of Michigan. Envisioned since the 1880s, the bridge was completed only after many decades of struggles to begin construction. Designed by engineer David B. Steinman, the bridge (familiarly known as "Big Mac" and "Mighty Mac") connects the city of St. Ignace on the north end with the village of Mackinaw City on the south. It is the longest suspension bridge between anchorages in the Western hemisphere.The bridge opened on November 1, 1957, ending decades of the two peninsulas being solely linked by ferries. The length of the bridge's main span is 3,800 feet (1,158 m), which makes it the third-longest suspension span in the United States and twelfth longest worldwide.
David B. Steinman was appointed as the design engineer in January 1953. By the end of 1953, estimates and contracts had been negotiated, and construction began on May 7, 1954. The American Bridge Division of United States Steel Corporation was awarded a contract of more than $44 million to build the steel superstructure.
Construction, which utilized the 1939-41 causeway, took three and a half years (four summers, no winter construction) at a total cost of 100 million dollars and the lives of five men who worked on the bridge. It opened to traffic on schedule on November 1, 1957, and was formally dedicated on June 25, 1958. The bridge officially achieved its 100 millionth crossing exactly forty years after its dedication, on June 25, 1998.
The 50th anniversary of the bridge's opening was celebrated in a ceremony hosted by the Mackinac Bridge Authority at the viewing park adjacent to the St. Ignace causeway on November 1, 2007.
