The Devils Tower, a national monument in Wyoming is next in my natural wonders series. It rises a sheer 1200' above the surrounding countryside. There are miles of hiking trails, fishing, and for those so inclined you are welcome to climb it.
You may think you have seen it before- it played a big backdrop part in Spielberg's epic Close Encounters of the Third Kind. I visited without any close encounters, but found it a jaw dropping experience.