Connecticut is about 1.4 times bigger than Yellowstone National Park.

Yellowstone National Park is approximately 8,983 km² (3,469 sq mi), while Connecticut is approximately 12,548 sq km, making Connecticut 40% larger than Yellowstone National Park.
Tip: This to-scale comparison of Yellowstone National Park vs. Connecticut uses the Mercator projection, which distorts the size of regions near the poles.
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