This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

Ruins of a German Castle on top of a towering stone pillar.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

A wunderkammer of curious objects and intriguing art nestled within a hub of ancient Roman sites.

One of the most important yet well-hidden museums dedicated to the history of medicine.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

The yawning maw of this pagan visage is said to bite off the hands of liars.

An alchemist's "magic door" stands in the middle of a Roman park.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Those who own or stay at this 500-year-old, allegedly cursed house often meet terrible fates.

The plague quarantine island home to the alleged "Vampire of Venice."

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

Abandoned Roman Catholic chapel abused by Satanists before being restored.

These temples are among the oldest free-standing stone buildings in the world.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

A US military accident created the legends behind this Mexican version of the Bermuda Triangle.