A colorful Peruvian city of the dead.

Popular tourist destination where witches in dark hats sell dried llama fetuses for good luck.

The remains of what was the most important religious complex in coastal Peru for over a millennium.

An ancient Incan convent on Lake Titicaca's Island of the Moon.

Keshwa chaca, among the last handwoven Incan bridges, crosses Apurimac Canyon in Peru.

A remote candy-striped mountain in the Peruvian Andes straight out of the pages of Dr. Seuss.

An Inca spa, military outpost or maybe… both?

Huge stone depressions which may have acted as an Incan agricultural experiment.

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

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

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

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

After this one-of-a-kind palace was built the architect's hands are said to have been cut off to keep it that way.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

This ancient subterranean megalopolis is known for the hot oil traps that were installed above each of its entrances.

While not Turkey's deepest underground city, this subterranean redoubt is the largest.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

This hunter-gatherer architecture is believed to be the oldest religious complex known.

A beautiful 19th-century Armenian mansion is preserved above an unassuming cafe.

"The prettiest love letters in the world" ... or so said Lord Byron.

A fake medieval village in the middle of Turin.

This mosaic-lined medieval church was built by the world's first admiral and still holds mass in ancient Greek.

People have been living in the cave houses on this Italian hillside since the Neolithic era.

Bell tower juts out from a village buried under a lake.