Natural time capsule containing an alien ecosystem.

This small chapel is built of human bones and decorated with a golden skeleton.

A gargantuan crystal kingdom.

The deepest hole drilled in the name of science, where evidence of Precambrian life was found.

A reproduction of earth's many biomes.

Former island in the Aral Sea used to be a top-secret Russian bio-weapons facility.

This pseudo-steampunk weapons facility is the world's largest wood and glue structure, and packs quite a wallop.

A Texas-sized particle collider that was abandoned due to its Texas-sized budget.

The second-deepest known cave on Earth, hidden in an extremely remote mountain region.

On the outskirts of a desert trading village high on the Andean plain, steel giants have been destroyed by salt winds.

Sacred Buddhist home of some spiritual monkeys.

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

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.