The Neapolitan Cult of the Dead still cares for the skulls at this mini-Fontanelle.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

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

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

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

This is the oldest Roman-made bridge in the city still existing in its original state.

The "Great Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

A rare example of a medieval house in Rome adorned with a melancholic inscription.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

This curious, round temple is the oldest still-standing marble building in Rome.

Rome’s legendary peephole vista is also a former Crusader stronghold.

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

Huge abstract sculptures of the Puerto Rican Flag.

Former bath house turns gastropub.

These mansions date back to Chicago's days as a brewer's paradise.

A giant bronze coil of feces is both a tribute to doggie defecation and a reminder to pick it up.

The legendary building that needed ghostly approval before being built.

Historic funicular railway, believed to be the shortest railroad in the world.

An artist's vision for connectivity spans seven continents and 16 countries.

Located on 420 acres in the high desert, this spiritual center is dedicated to the "science of the future."

A giant donut stands as a popular symbol of Los Angeles iconography.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

A common entry point to the Griffith Observatory trail holds its own wonders.

High on a hill overlooking Los Angeles lives a world famous, high-power conical Tesla Coil.