Montenegro is about 34 times bigger than Heard Island and McDonald Islands.

Heard Island and McDonald Islands is approximately 412 sq km, while Montenegro is approximately 13,812 sq km, making Montenegro 3,252% larger than Heard Island and McDonald Islands.
Tip: This to-scale comparison of Heard Island and McDonald Islands vs. Montenegro uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Montenegro vs. Heard Island and McDonald Islands

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