Da Vinci's equestrian statue, 500 years in the making.

A popular legend claims that the famous pizza was invented at a restaurant in this alley.

The burial place of an obscure North African saint was turned into a macabre body preservation factory for the 17th-century Neapolitan elite.

Erotic art covers the walls of the largest ancient pleasure palace.

Ancient snack bar of the Roman Empire re-opened.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

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

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

This giant middle finger statue sends an unambiguous message to Italy's bankers.

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

2300-year-old Roman road connecting the empire.

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

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

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

This red light district plaza memorializes the Fab Four and their historic connection to the area.

A comedic homage to a beloved German actor.

A beloved street vendor is memorialized outside a German train station.

Renowned mathematician and physicist Carl Friedrich Gauss once worked at this observatory.

The man who gave his name to magnetic measurement is buried in the city where he did his best work.

A museum that chronicles the history of the Nuremberg Trials for Nazi war criminals in the building where the trials were once held.

A 1:2 billion-scale solar system leads visitors into this German university town.