British Indian Ocean Territory is about 3 times smaller than District of Columbia.

District of Columbia is approximately 177 sq km, while British Indian Ocean Territory is approximately 60 sq km, making British Indian Ocean Territory 33.9% the size of District of Columbia.
Tip: This to-scale comparison of District of Columbia vs. British Indian Ocean Territory uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: British Indian Ocean Territory vs. District of Columbia

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