Under a church hides a forgotten 13th-century ossuary containing the remains of around 2,500 people.

A small monument on the outskirts of Prague, where one of the bloodiest conflicts in the country's history was decided.

This Czech military museum is home to pink tank that was once a symbol of art and political rebellion.

A museum of alchemy and a basement laboratory all housed in an ancient building in a Gothic tower.

A church of bones, decorated with 40,000 human skeletons.

An eerie reminder to the horrors of World War II.

The footprint of a frustrated devil in Munich's Cathedral.

This little-known relic crypt holds stolen parts of a Roman Empress.

A mechanized clock where a man fights off a dragon, crab, and rooster.

One man's personal collection of KGB memorabilia is presented along with his strange viewpoint.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

When this former hospital pharmacy closed in 2013 it already looked like a museum, so they turned it into one.

A hidden three-foot-wide house separates these two regal churches.

A total of 14 men held the title of "president" before George Washington—their historical legacies are enshrined in the lobby of a hotel.

This massive mushroom has spent centuries eating its way across a huge swath of Oregon.

The steepest tramway in North America provides stunning views of the out-of-the-way Wallowa Mountains in northeastern Oregon.

These falls, sometimes called the "Niagara of the West," still put on a good show at the right time of year.

This 80.33 troy ounces of solid gold is believed to be the largest nugget from Oregon still in its original form.

The secluded site of a 1943 plane crash and amazing rescue is only accessible by hiking through the woods.

Tucked away on a scenic trail, a modest memorial honors one of the greatest writers of our time.

Despite his legacy of work in Spain, Cuba, and Florida, the larger-than-life writer's grave is a simple affair tucked in an Idaho cemetery.

A former gold rush boomtown has managed to stay in business for over 100 ramshackle years.

When in Idaho, sleep in a giant potato.