This rare volcano spews the strangest and (literally) coolest lava in the world.

These coffin-like Brutalist balconies were inspired by a nearby mine.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

The world's largest concentrated solar power plant.

Exploring the wilder, more passionate sibling of Erg Chebbi feels like discovering a secret sun-kissed planet from another galaxy.

Deliberately hidden for centuries, the magnificent Saadian Tombs were eventually uncovered in 1917.

Fortune tellers, snake charmers, poets, and storytellers all gather on this historic square in Morocco.

A fortified city, home to a remaining population of five families

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

It took 40 years to build this Eden-like garden in Marrakech, later restored by Yves Saint-Laurent.

A hidden three-foot-wide house separates these two regal churches.

Elaborate tile work in this railway station tells the story of Portugal.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

The rusted hull of a WWII German destroyer pokes above the surface in a Norwegian fjord.

This old KLM airplane cut into three parts was transformed into an eclectic airport gift shop.

Museum celebrating the ocean, with the largest wunderkammer dedicated to sea exploration.

The first memorial dedicated solely to the Black troops who fought for the Union.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Before Nixon, "watergate" meant canals.

The walls of the iconic dome are hollow and have a secret stairway.

Affectionately known as "Lord Bot," this historic statue has a cult social media following and rightly claims to be “the most metal inhabitant of the Wren Yard.”