Once the home of a hermetic monk, this cave now houses a small church.

A restaurant and observation deck built in a unique broadcasting antenna.

An old department store turned Nazi prison turned artist commune.

Cold war icon and onetime "hole" in the iron curtain.

Metro station with a claim to rock n' roll fame.

Ice cream stand, snack bar, and time capsule of milk conveyance.

Notorious artist squat renovated into legal studios.

A large circus museum with summer performances.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

Macabre astrological automaton clock dating to the late 1400s.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

This massive tea kettle was once a promotional stunt for the Oriental Teashop.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

This tumultuous Icelandic lava field looks so alien European researchers want to use it as a stand-in for Mars.

A sulfuric martian landscape that looks far better than it smells.

A stratovolcano located in the south of Iceland, with a long history of charted activity and a rich mythology attached.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

Three columns of volcanic rock shoot out of the ocean.

Medicinal spa created with the discharge from a geothermal energy plant.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

A musical instrument played by the sea.