Sierra Leone is about 405 times bigger than District of Columbia.

District of Columbia is approximately 177 sq km, while Sierra Leone is approximately 71,740 sq km, making Sierra Leone 40,431% larger than District of Columbia. Meanwhile, the population of District of Columbia is ~601,723 people (8.1 million more people live in Sierra Leone).
Tip: This to-scale comparison of District of Columbia vs. Sierra Leone uses the Mercator projection, which distorts the size of regions near the poles.
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