This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

A hip bar decorated with walls of golden skulls.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

Visit the ancient, mysterious Roman catacombs ... in the Netherlands.

A museum glorifying the life of Stalin, located in the city of his birth.

Rock-hewn monastery complex with hundreds of cave structures tucked away into the mountainside.

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.

One of the Leiden's oldest pubs is also the birthplace of the Heineken star.

A luxury hotel housed in a former 15th century Gothic church.

This unique bridge physically lifts a piece of the road into the air to let boats pass by.

Survival capsules find a second life as a unique hotel.

A Netherlands hotel where you can sleep inside a wine barrel.

The ruins of this Dutch castle sit atop a labyrinth of once-secret tunnels and passageways, dating back over 900 years.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

Hidden within a Netherlands crater is a stone bed that lets those who lie in it see the sky as a curved surface.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

Colorful and chaotic stacked hotel in North Holland.

This historic Amsterdam bar used to accept sailor's monkeys as payment.

A beautiful maze marks where three countries meet.

Museum preserving torture methods from the past.

A curious collection dedicated to human and animal anatomy and pathology.