This neon blue river gets its color from a unique mix of bacteria and volcano minerals.

Sloth rehabilitation center in the jungle of Costa Rica.

Sparkling, calcite-covered skeletons of children who may have been sacrificed to appease an angry god.

Uninhabited islet in the Caribbean is the sanctuary of giant lizards.

The site of a devastating modern-day mud volcano eruption that buried parts of a village.

This peculiar lake of pitch is so thick and viscous that one can walk on its surface.

A natural tidal swimming pool is ringed by bizarrely artistic lava rock formations.

These eclectic homes nestled into the cliffs of a Caribbean island were built entirely from scavenged materials.

Rusting, graffiti-covered tanks litter the beach of this island, once used by the U.S. military for target practice.

Millions of glowing microscopic organisms light up the waters of this luminous lagoon.

Thousands of Haitians travel to the waterfalls to ask the Virgin Mary of Mount Carmel and her voodoo counterpart Erzulie for healing in a yearly pilgrimage.

A violent name for a violent volcano.

Looking like nothing more than a cartoon deserted island, this tiny sandbar is home only to a single umbrella.

This trio of Dominican cave lakes comprise a colorful biosphere of natural life.

This mountaintop lake bubbles and steams in a perpetual boil, thanks to its direct link to the Earth's interior.

Send a postcard while vacationing with Satan.

Where a rare geological phenomenon created a section of rock that resembles a checkerboard.

The world's smallest drawbridge.

A tropical paradise once home to space exploration and military installations.

This whimsically named Vietnamese stream is closer to a walkway than a waterway.

Home of the unusual art of water puppetry, one of Vietnam's oldest curiosities.

These crumbling towers are some of the last remnants of a centuries-old Vietnamese culture.

This striking landscape in northern Vietnam contains both geological and archaeological wonders.

A desert in southeast Asia, complete with a beautiful lake covered in lotus flowers.