Monument to a brutal, ineffectual US bombing campaign and a sobering reminder of the human cost of the Vietnam War.

A New Hampshire grave with a grudge.

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

Hidden in the hills is a mysterious stone structure, known only to a few.

This unusually shaped mountaintop tower looks like a UFO floating over the city.

An abandoned bell tower in the middle of nowhere is the last testimony of a forgotten medieval village.

One of the largest busts in the world celebrates the German city's erstwhile namesake.

The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.

The forgotten tomb of the Peruvian rubber baron who was the inspiration for Werner Herzog's epic film "Fitzcarraldo."

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

This Bronze Age tomb makes the most unusual front garden fixture.

A small part of Russia that does not touch any other part of Russia.

A geological bull's-eye visible from outer space.

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

A long spiraling walkway winds through the woods, and around a copper beech tree at the center.

Europe's largest natural bridge has a 19th century royal chateau built into its side.

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

Budapest's Communist-era statues, banished to the suburbs.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

A grand Yugoslav memorial to the group of partisans who fought and died resisting western Serbia’s Nazi occupation.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

A rusted metal giant pays tribute to Birmingham’s industrial past.

At the point of oceanic inaccessibility, you can't get farther from dry land without leaving the planet.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.