The mark of the Devil's horns on a marble column in Milan.

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

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

Before there were doorbells this bronze ear was installed for visitors to announce their arrival.

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.

When this funny little building went up in the 19th century, most people thought it would simply fall over.

A fake medieval village in the middle of Turin.

Where Venice's gondolas go for a tune-up.

The marble facade hides a little-known medical museum with early surgical instruments and rare copies of canonical texts.

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

The only museum with its curator—and her pets—buried inside.

The small peaceful island off the Venice tourist circuit is where the city began more than 1,500 years ago.

This abandoned island off the Venetian coast has been a radical monastery, a political prison, and a secret Nazi base.

100 year tradition of fist fights, marked by marble footsteps.

The plague quarantine island home to the alleged "Vampire of Venice."

Go inside to really appreciate this 500-year-old technological masterpiece.

As can be expected from a centuries-old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

Venice's "Island of the Mad."

This community on a small Venetian island has taken to painting their houses in bright neon hues.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

In Florence's great Duomo, a 26 foot fresco honors a mercenary famous for attacking Florence.

Overlooked amid the tourist bustle of Florence, this museum is dedicated to the craft of stone inlay.