U.S. national park of the day: Carlsbad Caverns
This park hides most of its wonders underground.
It has more than 100 caves, including the famous Big Room, one of the largest cave chambers in North America.
Descend deep below the desert and explore enormous limestone formations.
Stalactites, stalagmites, and underground chambers that took millions of years to form.
It feels like another world, right here in America.