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

Grand Canyon National Park is approximately 4,863 km² (1,878 sq mi), while Long Island is approximately 3,566 km² (1,377 sq mi), making Long Island 73.33% the size of Grand Canyon National Park.
Tip: This to-scale comparison of Grand Canyon National Park vs. Long Island uses the Mercator projection, which distorts the size of regions near the poles.
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