Fountain where visitors can earn a license to be mad.

Eco-village hidden in the foothills of the Alps that created a massive system of psychedelic underground temples.

The walls and streets of the ancient city are peppered with penises.

An eerie, little-known Neapolitan museum filled with preserved human remains.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

The steel cable lets adventurers zoom between two mountain towns at speeds of up to 75 miles per hour.

One of the world's oldest working clocks is curiously missing the Zodiac sign of Libra.

The first botanical garden, a feather in the cap of the Grand Duke of Tuscany.

A slightly creepy gallery of plaster cast models in the same museum as Michelangelo's David.

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

A factory director designed what was the world's longest suspension footbridge in 1923 so his employees could get to work safely.

Beautiful views and Roman-style statues on the Italian coast.

Crossing this suspension bridge feels like walking through the sky, a fitting tribute to the head of the Apollo program.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

This abandoned Brutalist treehouse is a hidden architectural relic.

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

Romans built the world's tallest artificial waterfall in 271 BC.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

Medieval torture techniques with a modern conscience.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

The famous sculptor left his mark on this Italian wall in an internationally protected example of street art.

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

This medieval Italian town is a sheer (and beautiful) cliffside defense.

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