This desert hasn't seen rain in 2 million years

The McMurdo Dry Valleys in Antarctica have not seen a single drop of rain or a snowflake in nearly two million years. While the rest of the continent is buried under miles of ice, these valleys are bone-dry dirt and rock.

This happens because of Katabatic winds. Gravity pulls heavy, cold air down from the mountains at speeds of 200 miles per hour. As this air rushes down, it heats up and evaporates every molecule of moisture in its path. It is essentially a giant, freezing blow-dryer.

The air here is so devoid of water that the Sahara Desert looks like a swamp by comparison. NASA uses this landscape to test Mars rovers because the conditions are the closest match to the Red Planet found anywhere on our globe.

If an animal wanders into the Dry Valleys and dies, it doesn't rot. There is no moisture for bacteria to thrive, so the bodies simply mummify. Seals have been found in the middle of the valley that look like they died last week, but carbon dating reveals they have been dead for over 700 years.

Deep beneath this dry surface lies a salty lake five times saltier than the ocean, which never freezes despite being far below the temperature of ice.