A surprising and unconventional mosque hidden in the subsoil of Istanbul.

This hidden gem is bathed in beautiful natural light.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

Quite possibly the oldest love poem known to humankind.

This half-forgotten fortress was constructed by the Ottoman conqueror of Constantinople.

No one is sure if the world's fourth-largest diamond had been found in a rubbish heap or was pawned by Napoleon's mom.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

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

An Art Nouveau gem hides beneath the layers of city grime obscuring this once-magnificent building.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

Legend says if you stick your thumb in the hole and it gets wet your wish will be granted.

1513 Turkish world map, full of European state secrets and snarky commentary.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A meow-velous tribute to a beloved street cat, made famous on the internet.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

The ornate miniature mansions were built for Istanbul's feathered residents.

A marvel of Byzantine engineering under the streets of Istanbul.

An alien landscape on the banks of the Aegean Sea.

Cave on extinct volcano, once home to famous mathematician Pythagoras.

Swarms of dainty flying insects swarm into the Petaloudes Valley to get busy.

This little Greek plateau is home to thousands of rustic, white-sailed windmills.

According to myth, Zeus himself was hidden in this cave to escape being eaten by his dad.

Hidden in a secluded Greek cove is a pristine beach marred only by the rusting smuggler's hulk stranded on its shores.

Monasteries on rock pillars, once accessible only by frayed ropes.