One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

An architect's childhood fantasy treehouse made real.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

The blood-soaked ruins of the castle where the murderous Blood Countess was walled in alive.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

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

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

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

Macabre astrological automaton clock dating to the late 1400s.

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

Steadily reminding Czechia of its past.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Countless grotesque faces stare out from this eerie Prague art wall.

The soulless eyes of 82 bronze children stare on forever in remembrance of a horrifying World War II massacre.

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

Underneath the city that invented pilsners are a series of historic tunnels that have been storing beer for centuries.

Bohemian paradise covered in majestic forests.

A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

An ornate plague column – built to celebrate life – claimed the lives of numerous artisans during its construction.

Tiny communists hammer away on the Olomouc Astronomical Clock.

The sanctuary holds what was once believed to be the saint's incorruptible tongue.

The largest toy museum in Poland showcases Europe's history of childhood.

Abandoned substation turned village treasure.