2. Going Batty at Carlsbad Caverns National Park
Situated in the Guadalupe Mountains in New Mexico, the Carlsbad Caverns National Park is home to one of the world's largest and most stunning cave systems. More than 119 caverns have been discovered so far and they exhibit a staggering diversity of mineral formations and one, Lechuguilla Cave, even sports an underground laboratory for geological and biological processes. The Carlsbad Caverns National Park is not just a great place to visit for troglodytes - there are several amazing reef sections that rank among the best preserved on the planet, drawing scientific researchers from all four corners of the globe. So far ca. 800 species of plants have been identified, three of which are cacti registered on the international "endangered" list. Visitors with a keen eye might even catch a rare glimpse of cougars and cave swallows, as well as 357 other species of birds.