For over 40 years, this quaint little house has teetered on a rock in the middle of a river.

A Serbian church lit by chandeliers made of weapons.

Legends of treasure and spirits flow from this this fairy tale-like oasis.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

Structure built from the skulls of vanquished foes.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

The temple that withstood the Nazis.

One of the largest mines in Bulgaria is now home to a vast museum more than 100 feet underground.

An unfinished complex built for children from around the world sits abandoned on the Black Sea coastline.

Ruins of an early Roman Christian church dating back to the 4th to 5th centuries.

Rock carving created 1,300 years ago 75 feet off the ground.

A mysterious tunnel hidden in the shadows of a colorful, historic sanctuary.

Outstanding, eerie frescoes and decorations fill this 19th-century monastery.

In a long-dry lake bed, these groups of massive stone pillars bear a striking resemblance to clumps of everyone's favorite fungi.

The second-largest Jewish temple in Bulgaria was deserted after World War II, seized by the communist government and then abandoned again.

A spectacular Bulgarian cave resembling a devil's head with a waterfall rushing down its throat.

The ceiling of Prohodna Cave in northern Bulgaria affords a peek at the sky via two deity-sized-eye-shaped holes.

This massive concrete sculpture is said to be the heaviest communist monument on Earth.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The ruins of an abandoned crematorium haunt an eerie deserted German cemetery.

The remains of a failed attempt at medieval nerdery are hidden deep in the woods of Virginia.

A train station that was abandoned by the coal industry and was later converted into a cocktail bar.

A recently abandoned psych ward at the end of Sanatorium Road.

A once-booming Mississippi River town with a history of racial violence is now eerie and mostly abandoned.