I hate to agree with GA but Northern Wisconsin is absolutly beautiful, especially in the fall.

I also have always found the Badlands in South Dakota to be a strangly beautiful place. Sedona also ranks up there with amazing natural beauty. I'll even throw in with those that say the Southwest is their choice. There are streches of land where there is nothing man made in sight for miles and miles and for some reason in those places I find it seems appropriate and easier to actually talk to God and Thank him for the wonder of it all.