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

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

142 ceramic steps become a mosaic once a year.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

Two stone columns flank the grand Venice square, but there were supposed to be three.

This giant crucifix is like U2's Joshua Tree for Swedish death metal fans.

One man's quest to fix his toilet unearthed over 5,000 artifacts spanning more than 2,000 years of history.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

The biggest drug trafficking passage between Mexico and the U.S.

This Stockholm light tower can be controlled by anyone with a smartphone.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

Indents in the pavement are all that remain from a grisly death machine in Paris.

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

Two large posteriors in one giant statue.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

A whimsical bridge adorned with decorative dragons.

Italian poet Dante Alighieri is entombed in this small mausoleum in Ravenna, and his hometown of Florence has never been too happy about it.

This automated sculpture of two men peeing will spell out text messages with their micturition.

Macabre astrological automaton clock dating to the late 1400s.

Largest necropolis in the Mediterranean.

A 16th-century horror show built in a lovely Italian garden.

An exclusive waiting room built for the royal family in the 1920s is hidden in Milan’s central station.