This cubist Vienna church building looks like some sort of alien stonehenge.

A beautiful but toxic fountain of mercury.

A unique form of erosion created an uncanny landscape of boulders perched atop slender columns of clay.

This natural gas vent certainly earns its name as the smallest volcano in Italy.

Sleep amongst an abundance of art from the modern era.

An unusual house built using an iso-elastic membrane.

The mountaintop inspiration for Umberto Eco's "The Name of the Rose."

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

Geometry and mystery come together in an epic show of octagonal masonry.

A sulfuric hellscape in southern Italy.

Italian cave with exceptional acoustics and an unsavory history.

The world's most active stratovolcano is almost always erupting.

A volcanic old faithful, Stromboli has been erupting continuously for the last 2000 years.

Erotic art covers the walls of the largest ancient pleasure palace.

The giant skeleton sculpture is surprisingly well-traveled.

Eighteen mummies have stood guard behind the altar of this tiny church since 1833.

"Stairs of the Turks", a chalky white cliff eroded conveniently into stairs, allowing for easy pillaging.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

This Italian foot path winds through the mountains via 52 individual tunnels.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

A graveyard and memorial chapel for victims of leprosy.

This Rococo church is known as the most beautiful village church in the world, and does not disappoint.

After years of being casually peed on by humans, this tree is peeing back.

An ornate century-old elevator still connects the two halves of Bad Schandau.