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

The fishing boats that moor in this small lagoon enter and leave through a tunnel to the sea.

These temples are among the oldest free-standing stone buildings in the world.

Malta’s oldest sea water distillation building is now an architectural anomaly on the Sliema waterfront.

Eastern Bloc nostalgia, anybody?

While it would not look out of place among Serbian spomeniks, this massive Bulgarian monument commemorates one of their defeats.

The most metal church of all time was built in record time because of an international, pious pissing contest.

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

A magnificent, glittering building tucked into a tiny Bulgarian mountain town.

Now a ruin, this grand resort was coveted by a communist autocrat and an eccentric Japanese golfer.

Founded in the 4th-century, the town of Pernik plays host to the Surva Carnival⁠—a magnificent display of masked Kukeri dancers.

The Bulgarian royal family exclusively used this ornate, now-abandoned train station.

"Unity, Creativity, Beauty."

A museum glorifying the life of Stalin, located in the city of his birth.

With over 10,000 lights, this engineering marvel lights up the city after dark.

Take respite inside this jaw-dropping church while climbing the volcano where Georgia's Prometheus was once chained.

A cylinder monument with a spectacular vista commemorates a friendship that some say never existed.

Fortified homes of highland warriors that are still in use today.

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

At this 16th-century monastery in rural Bulgaria, visitors can also spend the night.

This historic black and white monastery is one of Bulgaria's architectural jewels.

This tiny Bulgarian town offers a stunning location in the mountains and a storied history.

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

A gigantic statue of a Russian soldier watches over the ancient city of Plovdiv, a prominent reminder of the Soviet period in Bulgaria.