The abandoned "Ghost Mansion" was left to decay in the mountains of Northern Italy.

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

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

A once-luxurious, now abandoned hotel in the Italian Alps.

This half-finished "city of toys" was almost Italy's own Las Vegas.

Da Vinci's equestrian statue, 500 years in the making.

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

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

The topiary maze at the Habsburg hunting lodge.

The Grand Mall in Varna hosts one of the biggest collections of Soviet-era paraphernalia in Bulgaria.

Said to be the only museum in the world dedicated to the most classic of all blooms, the rose.

"Holy Wisdom" overlooks the city that became its namesake.

A gigantic statue of a Russian soldier watches over the ancient city of Plovdiv, a prominent reminder of the Soviet period in Bulgaria.

Rock carving created 1,300 years ago 75 feet off the ground.

A collection of art from Bulgaria's time as a communist state.

A space dedicated to contemporary art and culture, co-chaired by fashion icon Miuccia Prada.

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

Sitting on an Italian hilltop is this surreal fortress built by the mad inventor of electrohomeopathy.

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

A delightful architectural wonder awaits on a lake island in Kuala Lumpur’s oldest park.