Parts of Antarctica have had no rain for two million years, so it is considered the driest place on earth.
A desert is technically defined as a place that receives less than
254 mm (10 inches) of rain a year. The Sahara desert gets just 25 mm
(1 inch) of rain a year. Antarctica’s average annual rainfall is
about the same, but 2 per cent of it, known as the Dry Valleys, is
free of ice and snow and it never rains there at all.
Antarctica can also claim to be the wettest, since seventy per cent
of the world’s fresh water is found there in the form of ice.
The next-driest place in the world is the Atacama Desert in Chile.
In some areas, no rain has fallen there for 400 years and its
average annual rainfall is 0.1 mm (0.004 inches).