This extravagant villa built by a Burmese merchant is part pagoda and part European mansion.

The social hall of this former factory is a Communist-era time capsule.

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

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

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

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

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

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

Mysterious standing stone formations looks like a petrified forest.

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

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

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

UNESCO-protected ancient burial ground.

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

A striking symbol of the Bulgarian capital.

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

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

An ancient Thracian city where fire rituals were practiced on the largest cult altar in Southeast Europe.

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

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

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

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

South Korea's only sex-themed park.

A large-scale steel sculpture entitled 'The Shadow Boxer' pays tribute to Nelson Mandela.