Yellowstone, Grand Tetons, and Great Salt Lake in Utah
Yellowstone was enormous and I only saw a very small part of it, but what I did see was not nearly as impressive as I'd been expecting. I also learned about the great fire in 1988 they had, it's unbelievable how much damage it did back then and what some of the landscape still looks like 20+ years later. Grand Teton was unbelievably gorgeous and makes me want to head to Jackson Hole to go skiing sometime soon. Finally, Antelope Island on the Great Salt Lake was an interesting environment with magnificent views of the surrounding area. I had always assumed the Salt Lake was very built up and a huge recreation area (like almost every lake in New England it seems is), but it was surprisingly desolate.