North Dakota is about 1.8 times bigger than South Korea.

South Korea is approximately 99,720 sq km, while North Dakota is approximately 178,647 sq km, making North Dakota 79% larger than South Korea. Meanwhile, the population of South Korea is ~51.8 million people (51.2 million fewer people live in North Dakota).
Tip: This to-scale comparison of South Korea vs. North Dakota uses the Mercator projection, which distorts the size of regions near the poles.
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