Mackinac Island is about 19 times smaller than District of Columbia.

District of Columbia is approximately 177 sq km, while Mackinac Island is approximately 9.54 km² (3.68 sq mi), making Mackinac Island 5.39% the size of District of Columbia.
Tip: This to-scale comparison of District of Columbia vs. Mackinac Island uses the Mercator projection, which distorts the size of regions near the poles.
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