Mammoth Cave National Park is about 1.7 times bigger than Lake Norman.

Lake Norman is approximately 128 km² (49 sq mi), while Mammoth Cave National Park is approximately 219 km² (84 sq mi), making Mammoth Cave National Park 71% larger than Lake Norman.
Tip: This to-scale comparison of Lake Norman vs. Mammoth Cave National Park uses the Mercator projection, which distorts the size of regions near the poles.
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