A massive underwater sinkhole made famous by Jacques Cousteau.

Once a year in Pomuch, the dead are taken out for a cleaning.

Three sinkholes filled with warm, crystal-clear water reached by a horse-driven cart on an old train track through the jungle.

A hidden treasure of an abandoned city lies deep in the jungles of Campeche, Mexico.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

This 20th-century mansion plays a key role in one of Puerto Rico's greatest novels.

A French valley with forests so lush it was nicknamed "the Small Amazonia of the Pyrenees."

This restored colonial house was once home to the botanist responsible for bringing avocados to the U.S.

This hidden green space is the city's second largest conservatory.

The largest cactus farm in Africa.

An autonomous oak in Alabama.

Romania's "Red Ravine" is a little-known natural wonder that bears a resemblance to the Grand Canyon.

This garden is very fertile.

A mapping error in the 19th century made loggers think this section of the forest was underwater.

This grove of ghostly cedars was killed in 1700 by an enormous tsunami, felt from the United States to Japan.

Impressive sink holes fill this untouched old-growth forest in the Bahamas.

The remains of an abandoned dinosaur theme park litter the woods just off the highway.

It took an artist 20 years to create this sprawling sculpture garden honoring the area's ancient inhabitants.

A collection of 16,000 antlers crammed beautifully into a small shed.

Mystic Incan rock piles three miles above sea level.

This devil-dancing ceremony now celebrates a miraculous image of the Virgin Mary that appeared to a modern-day Robin Hood in a mineshaft.