District of Columbia is about 78 times smaller than Montenegro.

Montenegro is approximately 13,812 sq km, while District of Columbia is approximately 177 sq km, making District of Columbia 1.28% the size of Montenegro. Meanwhile, the population of Montenegro is ~604,966 people (3,243 fewer people live in District of Columbia).
Tip: This to-scale comparison of Montenegro vs. District of Columbia uses the Mercator projection, which distorts the size of regions near the poles.
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