An ancient city hidden in the heart of the Sierra Nevada mountains.

This elegant Colombian fortress was one of the torture headquarters for the Spanish Inquisition.

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.

In La Paz's huge, city-sized cemetery, the deceased are stored in rows of apartment-like buildings.

A desert that evokes the surreal.

Death road of Bolivia.

Bolivia's needle-like rock formations.

A valley of unique erosion patterns lends to a view like nothing on Earth.

Islanders once used this dramatic, otherworldly landscape to hide their cattle from Viking raiders.

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

The highest peak in the United Kingdom has a history of physics, specters, and a pilgrimage of strange objects.

Unfinished monument to peace between Turkey and Armenia, long divided by a dispute over genocide.

Over the centuries, this island paradise has done it all, from providing monks with ecclesiastical respite to sheltering an exiled Leon Trotsky.

A sacred lake with thousands of sacred carp and a biblical history.

Standing proud atop a Turkish bluff, this Ottoman palace has retained its grandeur despite being abandoned for centuries.

An abused and forgotten metropolis, abandoned for centuries.

A deadly ancient portal to the underworld.

Roman ruins top white travertine terraces formed by ancient hot springs.

An arresting arch punched straight through a mountain provides one of the most scenic spots, and challenging climbs, on the planet.

The largest wine cellar in the world is a 150-mile network of underground caves near the capital of Moldova.

A forgotten remnant of the Soviet Union, Transnistria is an unrecognized country hidden behind a heavily militarized border between Moldova and Ukraine.

This tiny museum's sizable collection is jammed into a former underground public toilet.

Where once there was a train station bathroom, there is now this German burger joint.