Spain is about 3.5 times bigger than Illinois.

Illinois is approximately 143,961 sq km, while Spain is approximately 505,370 sq km, making Spain 251% larger than Illinois. Meanwhile, the population of Illinois is ~12.7 million people (36.6 million more people live in Spain).
Tip: This to-scale comparison of Illinois vs. Spain uses the Mercator projection, which distorts the size of regions near the poles.
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