This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

Geothermal waterfalls in Tuscany.

Venice's "Island of the Mad."

Sitting on an Italian hilltop is this surreal fortress built by the mad inventor of electrohomeopathy.

Pompeii's less famous neighbor is still revealing her secrets.

Thousands of well-dressed mummies below a monastery.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

Stalactites and stalagmites in a beautifully lit cave.

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

Renaissance villa and gardens complete with a tormented colossus.

As can be expected from a centuries old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

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

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

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

A submerged archeological park still holds the wonders of a Roman Sodom.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

Architectureal fantasy quarter of Rome.

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

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

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

A 16th-century horror show built in a lovely Italian garden.

The remains of an attempt to carve a thriving metropolis from the forest, and once home to the first revolving door in North America.