Mackinac Island is about 6 times smaller than Manhattan.

Manhattan is approximately 55 km² (21 sq mi), while Mackinac Island is approximately 9.54 km² (3.68 sq mi), making Mackinac Island 17.5% the size of Manhattan.
Tip: This to-scale comparison of Manhattan vs. Mackinac Island uses the Mercator projection, which distorts the size of regions near the poles.
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