This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

Launched by Napoleon's soldiers more than 200 years ago, a cannonball remains embedded in the tower wall.

In an area known in Bratislava’s postal history, this sculpture sits equipped with a functional postbox.

The walls of this tiny Italian church are entirely covered with frescoes.

This poignant art installation raises awareness of violence against women.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

A brutalist gem towering over the heart of Milan.

This grisly effigy displays an early Christian martyr who was skinned alive and beheaded.

Small on the outside, big on the inside, this church is an astonishing act of visual deception.

This giant middle finger statue sends an unambiguous message to Italy's bankers.

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

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

This statue and park honor the Swedish chemist Jacob Berzelius, one of the founders of modern chemistry.

Stockholm's deepest subway station is also a stunning ecological wonder.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.