Iceland is about 582 times bigger than District of Columbia.

District of Columbia is approximately 177 sq km, while Iceland is approximately 103,000 sq km, making Iceland 58,092% larger than District of Columbia. Meanwhile, the population of District of Columbia is ~601,723 people (244,120 fewer people live in Iceland).
Tip: This to-scale comparison of District of Columbia vs. Iceland uses the Mercator projection, which distorts the size of regions near the poles.