Nature

One of the most extreme deserts in the world, these snow-free valleys harbor life, despite the hostile environment.

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

An arresting arch punched straight through a mountain provides one of the most scenic spots, and challenging climbs, on the planet.

Half of a waterfall goes into the river while the other half seems to disappear.

Unexplained bald patches in the landscape grow and recede over time, as though they are somehow alive.

This deceptively salty lake looks like blushing pink lemonade.

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

This peculiar lake of pitch is so thick and viscous that one can walk on its surface.

From the sky, a kaleidoscope of color brightens the grey landscape of the San Francisco Bay.

Rising from the sea like a stone monster.

Mount Nyiragongo has erupted at least 34 times since 1882 and is home to the world's largest lava lake.

A breathtaking canyon offers stunning views and frightful pathways through an ecological paradise.

Is it an island or a volcano? That question probably explains why it's uninhabited.

Walls of stone rise up from sinkholes caused by underwater erosion.

Numerous sculptures set along hiking trails symbolize and idealize the relationship between man and nature.

Iconic rock formations that allow for exploration during high or low tide.

A fiery-red region of scooped out land still largely untouched by civilization, tourists or otherwise.