A centuries old castle atop a dormant volcano houses museums devoted to both women and witches.

An extraordinary collection of 18th century anatomical waxworks.

A diverse collection of wax, bone, papier-maché and mummified relics.

Packed to the ceiling with antique taxidermy and hunting arms.

A stunning 18th century pharmacy and medieval chemist's collection.

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

This Croatian fairytale castle is slowly falling apart thanks to years of neglect.

Dynastic Home of the De Piro Family.

The former home of an Italian artist is now a shrine to his ambitious works.

Humble beginnings for one of the world's most famous scientists.

Roman-era ships unearthed...

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

Hideout of thieves, monks, and goat-footed gods.

Large collection from the 3rd millennium BCE.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

This legendary city has been a tourist attraction for centuries.

This historic black and white monastery is one of Bulgaria's architectural jewels.

A Red Cross memorial museum at the site of the Niš concentration camp that operated for four eventful years during World War II.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

A secretive collection featuring objects that were designed specifically for U.S. intelligence operations.

"There's nothing there," and other lies the KGB told us.

Museum dedicated to the UK's first charity for abandoned children, with keepsakes of the mothers who left them behind.

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

The glowing blue Nymphaeum of Emperor Tiberius.