An enigmatic modern marker left next to a historic Roman site.

An abandoned Roman salami factory has found new life as an art space home to 200 squatters.

One of seven Jewish catacombs in Rome and one of only two open to the public.

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

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

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

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

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

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

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

A hidden workshop for creating and restoring Papal mosaic masterpieces.

If you want to talk to the Pope you will have to stare down this surreal vision of Jesus rising from a nuclear hell.

The "first cat," "first dog," and even a presidential pygmy hippo all get their due in this museum.

This museum explores the grim reality of life in the earliest British colonies in America.

Where a guard killed nine German prisoners during one of the worst 20th-century POW camp massacres in U.S. history.

This museum sits on the site of a decommissioned military communications base.

An unusual number plate signifies the building's saucy past.

The narrowest street in Paris.

The tragedy of the Japanese internment camps is remembered here by a stark "Soul Consoling Tower."

This enormous "cloth of the conquest" depicts the Norman invasion of England in mind-blowing detail.

A daring D-Day assault by U.S. Army Rangers is commemorated atop the high cliffs of this strategic point.

A late sculptor's last project was to turn this abandoned cement factory into a castle-themed amusement park.

One man's unrequited love stands in a glass box forever.

The Magic House provides a beautiful and creative environment for curious youngsters to get their knowledge on.