The ancient tomb acts as a calendar that keeps perfect time.

The remains of Crystal Palace Great Exhibition of 1851.

A smoke stack so large, the Washington Monument could fit inside!

Rome's ancient Etruscan rival, now a park full of ruins.

Slaughterhouse Five opens its dank doors to fans of Kurt Vonnegut.

Terrifying derelict military hospital once housed a recuperating Hitler.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

Coastal dunes, site of buried Egyptian movie set and former utopian colony.

An Aztec temple, the largest man-made pyramid in the world, sits buried in earth with a Spanish church set on top.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

The Nazis lost more men trying to take this Russian-held Stalingrad apartment block than they did when taking Paris.

An ancient Viking village in North America that predates Columbus by 500 years.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

America's oldest archaeological site or a muddled case of wishful thinking.

This stately estate house features a tower covered in a bright, modern mural.

A Turkish ghost town abandoned in a population exchange with Greece.

An ancient Thracian city where fire rituals were practiced on the largest cult altar in Southeast Europe.

The tallest residential building in Africa is an unsettling Brutalist monolith.

Art Deco urban decay at this historical building.

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

This remote British Imperial telegraph relay outpost drove men insane.

A Roman monument to their own civil engineering prowess.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.