The underground sanctuary of a mysterious ancient cult.

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

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

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

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