Grand Canyon National Park is about 1.4 times bigger than Long Island.

Long Island is approximately 3,566 km² (1,377 sq mi), while Grand Canyon National Park is approximately 4,863 km² (1,878 sq mi), making Grand Canyon National Park 36% larger than Long Island.
Tip: This to-scale comparison of Long Island vs. Grand Canyon National Park uses the Mercator projection, which distorts the size of regions near the poles.
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