This series of Armenian caves held the oldest brain, shoe, and winery in the world.

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

A geological oddity topped with a 2,000-year-old pagan temple.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

Underground monastery and fortress.

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

Small church on top of a huge rock column.

Despite being tiny and rural this Georgian airport looks like a sci-fi boondoggle.

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

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

These rare statues are one of the few remaining material witnesses to Old Prussian culture.

A mysterious emblem tucked in an small alleyway is actually the coat of arms of a heroic medieval family.

Burial site of a Jewish prophet revered in Iran.

This beautiful system of tunnels built into natural rock serves as a centuries old plumbing system.

17th century mosque for Shah Abbas' harem.

These little castles each held thousands of pigeons.

In this tiny Iranian town playing on the roof isn't just encouraged, it's the only place to go.

This abandoned Belgian fortress is purposefully being left to nature.

Sculpture designed by Turkish artist and professor Mehmet Ali Uysal.

This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

Devoted Buddhists can earn enlightenment in the next life by crawling through this symbolic nostril.

The small alleys in Lübeck's Old Town are a result of medieval urban sprawl.

This peculiar museum offers hands-on interaction with seemingly intangible principles of mathematics.

Steaming blood-red hot spring from hell.