A monument to the art of slicing people open.

A Bibliophile's Dream.

A speakeasy takes on Chicago's drinking culture.

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

A lush green oasis in the middle of Chicago.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

In the past, Renaissance sex workers were encouraged to entice customers on this bridge.

Armenian monks at an island monastery in the Venetian Lagoon make a rare rose petal jam.

According to local folklore, this Roman sepulcher was once a throne for the Devil.

A forgotten "city of water" underneath the famous Trevi district.

This large, circular tomb is the final resting place of the first emperor of Rome.

One of the most important yet well-hidden museums dedicated to the history of medicine.

A collection of objects supposedly singed by the hands of souls in purgatory.

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

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

Dynastic Home of the De Piro Family.

The fishing boats that moor in this small lagoon enter and leave through a tunnel to the sea.

The remains of a 1st-century aristocratic Roman town house featuring beautiful well-preserved mosaics.

This defunct, fortress-like prison has been the setting for several movies.

A restored, one-room African-American schoolhouse in the diva's hometown now preserves the legacy of its most famous student.

The secret city built by the Manhattan Project.

Enormous lake at the bottom of a unique cave system.

An abandoned Indian-inspired mansion.

Now a pile of ruins and rubble, this was a lovely mountain town as recently as 1960.