One of the last Jazz Age "Wonder Theaters" in New York City.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

An ethereal glowing blue ocean cave in Croatia.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

The name of this famed hospital was once a byword for the horrors of medical and psychiatric care.

One of the oldest medical collections in Europe focusing on rare surgical instruments.

A monument to the art of slicing people open.

This Boston medical museum features the skull of the famous medical case of Phineas Gage.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

These fantastically named natural pools look like something out of a Scottish myth.

Nestled on the banks of a river in Nuremberg is a small museum that was once home of the city's official executioner.

A preserved college lock-up that recalls a clubhouse approach to discipline.

This German museum is devoted to all aspects of grave culture from headstones to coffins.

An intricate and amazing house built by architect Karl Junker.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

The most visited, and possibly most controversial, museum in Germany.

The birthplace of an eccentric alchemist and possible inspiration for the fictional reanimator of monsters.

On Japan's Tashirojima Island, cats are king.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Hot springs monkey spa in the middle of Hell's Valley.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."