District of Columbia is about 371 times smaller than Sri Lanka.

Sri Lanka is approximately 65,610 sq km, while District of Columbia is approximately 177 sq km, making District of Columbia 0.27% the size of Sri Lanka. Meanwhile, the population of Sri Lanka is ~23.2 million people (22.6 million fewer people live in District of Columbia).
Tip: This to-scale comparison of Sri Lanka vs. District of Columbia uses the Mercator projection, which distorts the size of regions near the poles.
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