Me to....I've been to the Smoky Mountains, Yellowstone, and Mt. Rainier, but the Smokies are the ones that I remember the clearest (I was pretty young when we visited the others), so I guess they'd be my favorite.
Ok, now I can compare. I've been to Yellowstone national park and, oh boy, that was a very exhaustive adventure, but I liked it very much. I would like to visit it again, but I guess I should pack my bag more thoroughly, according to this page. Though I don't remember the name of every mountain I visited there, but every view from it was gorgeous.Smoky Mountains indeed.