Two nations form a rare four-sided border at the peak of a mountain, philosophical questions result.

This stunning concert hall has become a symbol of Iceland's national recovery.

This is why we can't have nice things on the Incan Trail.

Tour the sci-fi-esque reality of governmental disease management.

This massive geographical sculpture is so subtle, it's possible to pass by it without noticing.

Earth's rocky history has rarely glittered so brightly as it does in this Spanish museum.

Because sometimes the most efficient route from A to B isn't a straight line.

A high school astronomy enthusiast designed this model of our solar system to be traversed on foot.

The stunning remnants of this wreck emerge from an otherworldly backdrop of rainforests.

The world's greatest slide descends 18 stories from this looping mountaintop viewing platform.

A proto micro-nation sometimes populated by artists, surrounded on all sides by a Utah most barren.

A spectacular annual festival centers around humans throwing molten iron against a wall at night.

Feed it cash, get your very own gold bar.

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.

A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

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

The most gigantic, swoony, intimidating trio of fingers in all of antiquity.

One man's labor of love, Amman's oldest home has become a time capsule with its doors permanently open to artists and guests.

The legendary luxury train passage is commemorated with a charming museum inside its former eastern terminus.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

In this truly magical place, rent hasn't been raised since the year 1520.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

Perhaps the world's only gas station inspired by a political scandal.

Oxford University's stateliest library seems designed to make students truly feel the weight of knowledge.