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

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

A vast Communist-era exhibition space in the Bulgarian capital.

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

"Unity, Creativity, Beauty."

"Holy Wisdom" overlooks the city that became its namesake.

Eastern Bloc nostalgia, anybody?

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

This once-grandiose behemoth of a monument from the socialist era now sits quiet and closed up.

A collection of art from Bulgaria's time as a communist state.

A striking symbol of the Bulgarian capital.

A flamboyant five-story building in Bulgaria resembles a crawling snail.

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

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

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

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

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

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

An abandoned saucer-shaped monument in the Bulgarian mountains.

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

This natural spa is known for its healing properties and vibrant hue.

The elliptical citadel resisted the advance of the mighty Ottomans several times, thanks to the military prowess of the "Dragon of Albania."

Once the fallout shelter of a dictator, this sprawling bunker is now a combined history museum and contemporary art gallery.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.