This clifftop arch is a natural stunner.

The Emperor Tiberius' palace of debauchery.

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

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

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

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

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

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

A spherical "micro-nation" in the heart of Vienna.

Collection dedicated to funeral rites, equipment, and mourning rituals of the Viennese.