Stalin's secret bunker.

A dormant lightning machine equal to all the power in Russia.

The coldest city in the world.

Siberian ghost town built by gulag prisoners.

Secret Soviet city once home to Russian cosmonauts and space training facilities.

Nightmarish example of the unintended consequences of weapons testing.

Moscow's other, lesser known kremlin is a fairytale-like cultural complex modeled after Old Russia.

Dr. Strangelove-esque tours reveal the inside a bunker once reserved for Stalin himself.

The mouldering remains of a disgraced British children's icon are hidden in the brush of a public park.

This abandoned-looking amusement park is frighteningly open for business.

North Korea's massive "hotel of doom."

A symbol of the Workers' Party of North Korea.

A massive 1830s industrial site once known as Czechia's "Iron Heart" has been transformed into a playground of science, technology, and art.

These mysterious 1,000-year-old walls have revealed little about their past.

A magical place that lets you play in and explore the world of Studio Ghibli.

The remains of the great moral philosopher reside in a university in London.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

The Nobel-Prize-winning author of The Stranger is buried beneath a simple gravestone in a sleepy French village.

This Manchester laundromat is hiding something.

The awe-inspiring ship from the golden era of cruising has an incomparable history and a reputation as one of the world’s most haunted places.

The dining hall that nourishes workers in Chernobyl's Exclusion Zone is also open to visitors.

This attraction was abandoned after the Chernobyl disaster.