A fairy tale castle in modern Rome.

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

The ruins of an abbey believed to have been founded by Charlemagne in the 9th century.

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

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

The final resting place of the poets Shelley and Keats.

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

An artist's mausoleum with a haunting echo.

The former home of Norway's greatest romantic composer.

Ruins of two abandoned stations destroyed by the power they sought to harness.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

A Viking-style brewpub named for a Norse sea giant, in the heart of fjord country.

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

The underground sanctuary of a mysterious ancient cult.

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

A huge enchanting public park just outside the ancient walls of Rome.

This natural rock formation features seemingly unnatural vertical ridges that have been blamed on elves.

Between Neo-Pagans and Neo-Nazis, these strange rock formations have a curious cult following and a very strange history.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

This unique Renaissance castle was turned into a home for Nazi occultism.

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

A self-built mosaic house and sculpture park.

This stunning French estate was so lavish that it landed its original owner in jail for the rest of his life.

A mosaic-tiled house built by graveyard sweeper Raymond Isidore.