I've never been to Iceland so unfortunately can't tell! I absolutely wanna go there someday.
The vulcanos and geisers are actually ludacris.
I think one could also make a case for USA being one of the most beautiful countries in the world because of it's diversity, u literally have everything from snowy mountains to wild forests. But in the same sentence, i would say it's unfair, because it would be like comparing a whole continent against a country like say Iceland, Norway, Switzerland, Nepal, Peru or Japan.