Shouldn't Antarctica be the driest desert on Earth?

The McMurdo Dry Valleys is a small section of Antarctica. This place is commonly referred to as the driest place on the earth. They are referred to as such because of their low humidity and that they lack both snow and ice cover. It would certainly be hard to believe this, but the Sahara Desert could not even be put on the top ten list of the driest places on the earth.

This is a fact that is much beyond common understanding. You see, there is this limited area of the Antarctic that has such features. But their Dry Valleys are really the world's driest place.