The bridge opened on November 1, 1957, connecting two peninsulas linked for decades by ferries. A year later, the bridge was formally dedicated as the "world's longest suspension bridge between anchorages", allowing a superlative comparison to the Golden Gate Bridge, which had a longer center span between towers, and the San Francisco–Oakland Bay Bridge, which had an anchorage in the middle.
It remains the longest suspension bridge with two towers between anchorages in the Western Hemisphere. Much longer anchorage-to-anchorage spans have been built in the Eastern Hemisphere, including the Akashi Kaikyō Bridge in Japan (6,532 ft or 1,991 m). But the long leadups to the anchorages on the Mackinac make its total shoreline-to-shoreline length of five miles (8.0 km), longer than the Akashi-Kaikyo (2.4 mi or 3.9 km).
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 20th longest suspension span worldwide. It is also one of the world's longest bridges overall.