Geology

A strange rock in Chicago marks the spot where a tree once stood in honor of the 18th President.

Plains of ash and pair of semi-active volcanoes contribute to the otherworldly beauty of this little-known Vanuatu island.

According to the locals, the sands of this secluded Norway beach are infused with gemstone particles.

This haunting stone chasm is a hotbed of mossy rock and English legend.

This Portuguese bullring is built right into the caldera of an island volcano.

This punny mirror of another Wisconsin attraction is exactly what it sounds like.

This Irish show cave is said to have been the site of a Viking massacre that claimed 1,000 lives.

This controversial Irish show cave is home to a massive formation known as the Great Stalactite.

The first space rock known to have struck a human.

This ancient Hawaiian henge may have been an early star chart.

These jagged limestone blades cut out through the canopy of the jungles of Borneo.

This huge pile of volcanic boulders hides a stunning network of secret grottoes.

This mysterious petroglyph evokes the ancient swastika symbol but was later vandalized with the more troublesome Nazi one.

This electric green sulphur lake in New Zealand looks like a cartoonish radioactive dump site.

Possibly the oldest of Britain's ancient henges is also one of its most stark.

Tiring of digging out the door to this church for every service, it was eventually abandoned to the sands.