Mammoth Cave National Park is about 1.2 times bigger than Aruba.

Aruba is approximately 180 sq km, while Mammoth Cave National Park is approximately 219 km² (84 sq mi), making Mammoth Cave National Park 21% larger than Aruba.
Tip: This to-scale comparison of Aruba vs. Mammoth Cave National Park uses the Mercator projection, which distorts the size of regions near the poles.
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