The remains of one of the last mining camps developed on the New River.

These old towers extract salt from the sea.

The graffiti-covered ruins of an abandoned trading post in the middle of Navajo Nation.

In Spain, the ruins of a Roman military camp sit along a flooded section of a river.

An abandoned mine now resembles a post-apocalyptic landscape of derelict buildings and blood-red pools of water.

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

The ruins stand as a somber reminder of France’s worst civil catastrophe of the 20th century.

An architect transformed this abandoned cement factory into his castle-like workshop.

This abandoned racetrack looks like it is set to hold competitions in the apocalypse.

A pair of connected skyscrapers form this symbolic gateway.

The fairy tale castle of the "fairy-tale king."

An eerie, derelict amusement park in Berlin.

This abandoned fighter jet launch center is now a haunting street racing course.

This declassified Cold War bunker hosts a large collection of Swedish aircraft.

This French chateau is home to the world’s largest private collection of fighter jets.

An old airplane engine forms an unusual cairn atop this Moroccan peak.

Ghosts of France's colonial past.

The abandoned ruins of a beautiful medieval castle just outside Barcelona.

This abandoned gun tower was built to defend the River Thames from a French naval attack.

A giant gun barrel in Barbados that once hoped to shoot outer space with science.

The 1936 Summer Olympics site is a crumbling remnant of sportsmanship and a history its host country would like to forget.

Built to be the ideal penitentiary, this abandoned panopticon saw several revolts and even a prisoners' coup.

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

Obscured within a ring of trees, this abandoned World War II relic hides on a German hillside.