Moss and stone turn this waterfall into an otherworldly liquid veil.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

This apartment is a true time capsule of local life in Bulgaria during the Soviet regime.

A massive cave once a secret military base is now home to thousands of bats.

On the outskirts of the small village, an abandoned grassy field glitters thanks to the white stones of an ancient structure.

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

Not far from a popular beach, an unfinished, abandoned mansion for Bulgaria's last communist dictator.

These natural cliffs look like they are a part of an old castle complex.

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

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

The remarkably well-preserved final resting place of a powerful ancient Thracian king.

Mysterious standing stone formations looks like a petrified forest.

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

UNESCO-protected ancient burial ground.

The site of many battles and tragedies, including the 40 maidens who leapt into the sea.

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

Bizarrely shaped rock formations in northwest Bulgaria come with equally bizarre legends.

An architectural marvel that spans the Arda River, and has stories of a haunted past.

An abandoned saucer-shaped monument in the Bulgarian mountains.

Stelae-eyed stones greet visitors to a corner of Kirov Park.

This was once the largest city in Kazakhstan, and a major stop on the Silk Road.

A collection of Lenin busts and other Soviet Era statues sit idly behind the Semipalatinsk Hotel.

One of the most horrible legacies of the Cold War is a site where the Soviet Union tested nuclear bombs on civilians.

Mysterious spherical rocks in the semi-desert of western Kazakhstan.