An abandoned Byzantine fortress and notorious prison.

Thousands of rusting train cars have been slowly falling apart on the edge of Greece's second largest city.

This field of half-buried stone crosses was the burial place of a sect of heretical gnostics.

A peculiar samurai statue overlooks the center of Brno.

This strange statue depicts a young boy's body with an adult Mozart's head and a single wing.

A cheeky architectural easter egg.

A former top secret nuclear fallout shelter now operates like a hotel stuck in the Cold War.

The United Arab Emirates's biggest and oldest fort pays homage to a lost era.

The oldest surviving mosque in the UAE has mysterious origins and unusual architecture.

One of the largest sand dunes in the world is nicknamed the "Scary Mountain" due to its steep slope and sharp incline.

Whitewashed mosque contains the world's largest carpet.

This enormous sports car themed amusement park is home to the world’s fastest roller coaster.

Planned as the world’s first zero-carbon city, it had lofty ideals—but is only 5 percent completed and aiming for 50 percent carbon-neutral.

This indoor ski resort has a mountain contained inside a mall.

On any given day this sprawling market houses literally tons of government-regulated gold, gems, and precious metals.

A massive collection of petroglyphs dating back some 40,000 years.

The village's cobblestone streets are lined with shops displaying exquisite copper craftsmanship.

This mysterious but iconic tapered tower appears in many Azeri fairytales and legends.

Swirling layers of white and red rock earned these mountains their festive nickname.

This burial cave houses around 100 ancient coffins, neatly stacked to form a massive wall.

This belfry is all that remains of the town that was buried by a violent volcano eruption.

These Stalin-era industrial 'death traps' hang lifeless above the city

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

Tall columns of volcanic basalt make up this improbable-seeming rock formation.