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

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

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

A highland eco-park celebrates more than a thousand varieties of tuber.

The Incas turned this ancient Wari aqueduct into an imposing defensive gate.

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

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

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

The mortal remains of an estimated 70,000 people lie in the basement of a monastery in Lima, Peru.

Law-protected wreckage serves as a peculiar memorial for an almost forgotten World War II tragedy.

This world-class vineyard has a peculiar collection of contemporary sculptures scattered across the property.

The unedited photograph called "Bliss" has graced the screens of over a billion computers.

The largest drain hole in the world.

Wheels of chrome by the thousands adorn this California Historical Landmark.

Rising out of miles of farmland, these buttes are sometimes called the world's smallest mountain range.

One of the largest fleets of armored vehicles in the world, sitting out in the California desert.

A breathtaking 19th-century trail overlooks Lake Tahoe.

A scenic hike in the High Sierra that ends at an old gold mine.

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

This solitary monastery may hold the remains of Vlad the Impaler (but probably not).

This enormous abandoned prison was once dubbed the "Bastille of Romania."

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

An abandoned saucer-shaped monument in the Bulgarian mountains.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.