Thousands of narrow alleyways in an ancient medieval city make up what's believed to be the world's largest car-free urban zone.

An awe-inspiring mosque in Morocco with one of the tallest minarets in the world.

God's Saharan sandbox of wrath.

Traditional 11th-century outdoor tannery.

World's largest film studio, where visitors tour the decaying sets that litter the harsh desert environment.

One of the most spectacular canyons in the world.

A 18th century graveyard and its astonishing cortege of macabre iconography.

The final resting place of soldiers' loyal canine companions.

Most prolific publishing house in the 1600s open to the public.

A treehouse assailed by the elements and the government, now gone.

Secret hideaway for an alternative beach experience.

A museum dedicated to the exploring past, present, and future innovations.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

A sulfuric martian landscape that looks far better than it smells.

This tumultuous Icelandic lava field looks so alien European researchers want to use it as a stand-in for Mars.

This elegant arc of a waterfall marks a religious turning point.

These ominous lava formations were said to be an entrance to the netherworld so of course they inspired a famous metal band.

This black church sits alone among a field of lava rock.

This collection of unique liquids allows visitors to wander the waters of Iceland's glaciers.

This scenic Icelandic lava flow is named for a pair of Berserkers who were murdered, according to a famous Saga.

A historic freight system that found the true gold rush is in tourism.

Budapest's Communist-era statues, banished to the suburbs.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

A museum dedicated to exhibiting remarkable outsider art.