The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

Sleep in a glass pod dangling off a cliff.

Nazca pilgrimage site covering 370 acres is a popular stop for archeologists and looters.

An unexpected desert oasis in South America.

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

A market for witches is hidden within a train station.

A set of ancient drawings in the desert of Peru that are so massive, many of them can only be fully seen from the sky.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

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

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.

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

The one-time stronghold of the noble Douglas family, now home to ghost sightings and nesting birds.

A book bound in the skin of an infamous criminal, along with countless other specimens.

A church that bred legends, and served as an inspiration for the Da Vinci Code.

The ruins of this gorgeous clifftop castle look like something from a fantasy novel.

Now famous as the "Harry Potter bridge," this impressive concrete viaduct has long been an icon in its own right.

A 30-acre garden inspired by the principles of modern physics.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

100-year-old shipwreck you can walk up to at low tide.

An ancient Egyptian temple in the middle of Madrid, Spain.

Built to hold the worst of the worst of the Nazi war prisoners.

This bronze statue was erected to honor a small Scottish town's beloved stray cat.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.