United States is about 44,989 times bigger than Mammoth Cave National Park.

Mammoth Cave National Park is approximately 219 km² (84 sq mi), while United States is approximately 9,833,517 sq km, making United States 4,498,751% larger than Mammoth Cave National Park.
Tip: This to-scale comparison of Mammoth Cave National Park vs. United States uses the Mercator projection, which distorts the size of regions near the poles.

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