West Virginia is around the same size as Croatia.

Croatia is approximately 56,594 sq km, while West Virginia is approximately 62,361 sq km, making West Virginia 10% larger than Croatia. Meanwhile, the population of Croatia is ~4.2 million people (2.3 million fewer people live in West Virginia).
Tip: This to-scale comparison of Croatia vs. West Virginia uses the Mercator projection, which distorts the size of regions near the poles.