The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Sloth rehabilitation center in the jungle of Costa Rica.

If you’ve ever seen a picture of Machu Picchu, then you’ve seen a picture of Huayna Picchu—you just didn’t realize it.

One of the world's tallest waterfalls wasn't revealed to the world at large until 2006.

Sleep in a glass pod dangling off a cliff.

The world's fifth tallest waterfall is a spectacular silver chute of water that cuts through the cloud forest in northern Peru.

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

These giant mummies are set ominously into a Peruvian cliffside and topped with real human skulls.

A backdoor to Machu Picchu that only the most foolhardy infiltrator would attempt to breach.

White llama terraces dazzle in Peru's "other Machu Picchu."

These steeply terraced ruins are a stop along the Inca Trail to Machu Picchu.

One of the most remote lodges in the Amazon offers rare wildlife encounters and undisturbed views of the Peruvian rainforest.

The highest tropical mountain range in the world is in Central Peru, home to a vast array of exotic and quirky plants and animals.

This unimaginably large pile of sand near Nazca is one of the tallest dunes in the world.

Tucked behind the Institute of Neurological Science down a decrepit street resides the largest display of human brains in Latin America.

A jungle cave in Peru of unknown depths, otherworldly sounds, and strange nocturnal birds that navigate by echolocation.

Extraordinary rock formations in open Peruvian fields.

Lima’s Museum of Anthropology is lined with thousands of elongated human craniums.

An unexpected desert oasis in South America.

A remarkable geological formation resembling a forest made of stone.

Plundered and left asunder by grave robbers, this ancient necropolis has been painstakingly pieced back together.

This Peruvian canyon is filled with geometric salt pools that have been being harvested since the Incan empire.

A market for witches is hidden within a train station.

This scalding hot river was thought to be a myth until one geoscientist made it his quest to study the mystical waters.