Bahrain is about 4.3 times bigger than District of Columbia.

District of Columbia is approximately 177 sq km, while Bahrain is approximately 760 sq km, making Bahrain 329% larger than District of Columbia. Meanwhile, the population of District of Columbia is ~601,723 people (938,835 more people live in Bahrain).
Tip: This to-scale comparison of District of Columbia vs. Bahrain uses the Mercator projection, which distorts the size of regions near the poles.