Heard Island and McDonald Islands is about 1.6 times bigger than Cayman Islands.

Cayman Islands is approximately 264 sq km, while Heard Island and McDonald Islands is approximately 412 sq km, making Heard Island and McDonald Islands 56% larger than Cayman Islands.
Tip: This to-scale comparison of Cayman Islands vs. Heard Island and McDonald Islands uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Heard Island and McDonald Islands vs. Cayman Islands

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