The caldera of this mini-volcano has been turned into a naturally heated mud bath.

A 10 million-ton rock once worshiped by the Tahamies Indians, accessed by an astounding staircase.

Unparalleled stargazing, one of Colombia's best observatories, and a swimming pool can all be found in the middle of this ancient tropical forest.

The Andean town where every single building is decorated with a brightly colored frieze.

Enchanting cave with a river crashing through the roof.

A dangling church built over a Colombian gorge.

This picturesque mansion has gone from opulent ruin to nature museum.

An explosion of natural color known as "the river that ran away from paradise."

This ceremonial Mexican square looks as though it belongs in a science fiction movie.

An archaeological museum at the Aztec pyramid displays signs of the New Fire ritual performed every 52 years.

Detailed miniature models of iconic landmarks in Mexico and around the world.

Bright, rebellious indigenous murals dating back to the Spanish Conquest inexplicably cover the walls of this Catholic church.

These enigmatic columns tower over the ruins of an ancient Toltec city.

With nearly double the depth of the Grand Canyon, this Peruvian canyon is one of the deepest in the world.

One man spent 10 years building a spectacular section of road because no one else would.

The last manually operated turntable ferry in the world.

An ancient Scottish rock formation said to be the gravesite of a giant remains ensconced in legend and intrigue.

The symbol was surreptitiously built into the river bank by German prisoners of war.

A clear blue swimming hole with hidden caves, still unexplored.

A somber monument commemorates the site of a Native American reservation marked by suffering.

A small museum along the Susquehanna River is home to a rich collection of Native American artifacts.

Lines from a walking song are etched into a rock in Natural Bridge State Park.

This historic crypt was said to have been designed and built by the very person who is buried inside of it.

Though it's unclear why it's there, the lifelike sculpture of the giant lizard is oddly charming.