Ever hear of the Milazzo Cage?

At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

A collection of objects supposedly singed by the hands of souls in purgatory.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

The underground sanctuary of a mysterious ancient cult.

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

Harlequin costumes, signed scripts, and armor-wearing puppets.

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

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

St. Francesca Romana, patron saint of drivers, resides in the church she founded.

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

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

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

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

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

The childhood home of Earth's alien chameleon is a humble Brixton flat.

The monster at the center of the Darwin Center Spirit Collection.

English antique dealers with a taste for the unusual.

Repository for more than 22 million pickled specimens.

Eighty million natural history specimens call this gargantuan museum home.

This intricately carved and hilariously huge bed was such a famous symbol both Shakespeare and Byron used it in their writing.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

Catacombs turned marketplace.