This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

It houses the remains of a 17th-century version of the Titanic.

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

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

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

This sculpture marks the spot where one of the greatest Roman rulers was proclaimed emperor.

Follow the original medieval paths that wind through this intriguing section of the city.

The most loyal of little dogs, or a Victorian era publicity stunt?

A statue beloved by—and named by—the local townsfolk it represents.

An oversized, oddly designed pedestrian overpass has drawn comparisons to a commode for pachyderms.

The sweet story of how American cargo planes became known as "Candy Bombers" during the Berlin Blockade.

The entrance to this Frankfurt subway station looks like an old tram car crashed into the concrete sidewalk.

Fantastic views and thousands of love locks.

This historic stone bridge has an entire neighborhood clinging to its sides.

Beloved children's TV characters freckle the German city's streets.

A unique structure located on the grounds of one of five grand palaces that were built by the Joseon dynasty.