Unlike many reclaimed, abandoned mines, this Canadian cave system is still just a dangerous maze.

Every four years, millions of salmon fill a river so densely that its waters appear deep crimson.

This angular Dwarven tunnel cuts through a mountainside in Glacier National Park.

Possibly the world’s easiest Easter-egg hunt.

A surviving remnant of the thick ice mass that once mantled most of Western Canada's mountains.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

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

In the hinterlands of Serbia's capital, a giant reflective mushroom houses an aeronautical history of the former Yugoslav republic.

This lake in the Cascades lives up to its name, disappearing down a hole every spring.

A 605-page Quran penned in the blood of a dictator is locked away in a mosque.

A formerly glacier-tipped volcano that inspired none other than Jules Verne.

Earth's greatest purely vertical drop at 4,101 feet.

Neither bomb blasts nor heartbeats escape the giant ears of this super sci-fi Arctic outpost.

The world's largest neutrino telescope searches for secrets of the universe at the South Pole.

Natural time capsule containing an alien ecosystem.

Largest sub-glacial lake ever discovered.

These passages carved from the Antarctic ice hold strange shrines to the harsh southernmost climes.

This Japanese-inspired labyrinth of hot springs is hidden in a Chilean forest.

This Argentinian hedge maze is an intricate tribute to a famous surrealist author.

This historic Chilean cemetery is the burial place of hundreds of European and American freethinkers and non-Catholics.

A beautiful deserted greenhouse in the middle of a park.

The bookstore with bookshelves built into unlikely places.

One of São Paulo's tight urban intersections has become a haven for graffiti artists ever since a single Batman started the trend.

After millennia of erosion by sand and churning water this Brazilian valley now looks like a lunar fantasy.