Two very green residential towers cleaning the air in one of Europe's most polluted cities.

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

One of the world’s smallest bars, just 13 square feet, is brimming with speakeasy flair.

The odd depiction of the Virgin Mary and baby Jesus is rooted in the Catholic Church's eradication of Catharism.

This poignant art installation raises awareness of violence against women.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

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.

The secret medieval communication system will whisk your words above the noise of the crowd.

This camera store in Milan holds one of Europe’s largest collections of luxury-antique cameras.

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

Just across from the "Last Supper" painting is the famous painter's vineyard, a gift received for creating the masterpiece.

A larger-than-life house of cards stands outside the house of a former fashion designer.

Inside a former cabaret, seven floors of erotic art.

A poem by Arthur Rimbaud is inscribed on the wall of a street that, while it is only one block long, plays a key role in multiple novels.

One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

A mechanized clock where a man fights off a dragon, crab, and rooster.

One of Jeff Koons’s largest sculptures and his first commemorative work.

This lesser-known Frank Gehry building houses a treasure trove of cinema history.

The video game-themed street art first popped up in the French city.

A French artist's vague warning hangs over Belleville.

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

This structure atop a craggy cliff in one of the most beautiful parks in Paris boasts an unbeatable view.