O'Hare Airport is about 2.9 times bigger than Mackinac Island.

Mackinac Island is approximately 9.54 km² (3.68 sq mi), while O'Hare Airport is approximately 27 km² (11 sq mi), making O'Hare Airport 187% larger than Mackinac Island.
Tip: This to-scale comparison of Mackinac Island vs. O'Hare Airport uses the Mercator projection, which distorts the size of regions near the poles.
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