A historic and beautiful Art Nouveau chamber in a historic railway station.

One of the famous Czech artist's lesser-known Prague installations appears to be a glowing fetus affixed to a drainpipe.

A Jenga-style cylindrical tower of books that appears to go on forever.

Nine bronze hands protruding from a wall honor the student uprising that led to the fall of Czechoslovakia's Communist government.

Macabre astrological automaton clock dating to the late 1400s.

This spooky statue sits outside a famous Prague theater.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

An existential riddle in the world's largest ancient castle.

The hidden lair of an alchemist rediscovered in a 2002 flood.

The first museum in the world devoted to sexual gadgetry.

Near the site where the English Archbishop was born, you can find an emblem in the shape of a pilgrim's badge.

Tombstones and enigmatic inscriptions hide within a vault beneath a popular London arts venue.

Victorian-era Londoners really wanted to believe this 17th-century cistern was actually an ancient artifact.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

A discarded movie prop that was the original monolith for "2001: A Space Odyssey."

An architectural oddity hides in plain sight on this iconic London bridge.

A memorial for public executions that dates back to the 14th century.

The barrel-made lookout from Shackleton's final ship is tucked away in the crypt of one of London's oldest churches.

This pub has roots dating back to 1430 and serves as the setting for multiple Charles Dickens stories.

Shiny Brutalist box commemorates a pioneer of electricity and houses a railway transformer.

At the center of London’s oldest roundabout stands an obelisk that was erected in 1771, but spent several decades elsewhere.

The history of this famed tree ranges from an 18th-century highway robber, to the Scout Association.

The extra platform at Gloucester Road has been used for art displays for over 25 years.

This statue in Holland Park might be one of London’s oldest outdoor statues, but its exact origins are unknown.