Number 5: Probably the best known cave in the world and for good reasons. Located in Southeastern New Mexico, this National Park draws over 700,000 visitors each year. With over 20 different chambers, or rooms, 16 species of bats, and an average summer temperature of a cool 58°. With rooms like “The Hall of the Giants”, an amazing 350,000 square foot cave. You could spend countless hours, if not days exploring this national treasure.