This is obviously an opinion, but I think Iceland. I've been to the alps in Switzerland and Italy and stuff (that's very breathtaking), but Iceland is so unique in its landscape. Iceland is my favorite place I've ever been.
Im rather partial to the USA myself. In what other single country do you get everything from tropical rainforest to huge snowy mountains to coastal fishing villages to high plains to high desert to massive giant trees to even more massive canyons to some of the most amazing natural rock formations in the world to vast, rich farm and ranch lands to ancient green hill country WITH most of its trees intact, to huge inland lakes, to some of the widest wildest rivers in the world? All in a SINGLE COUNTRY? Each of these exists in separate countries, yes, but nowhere else do ALL these beautiful, incredible natural wonders exist in a single country other than in America. God Bless the USA!