The Sahara, with a size of 8.6 million km², is the world's largest desert, covering large parts of North Africa. Around 4 million people live there. Its maximum length is 4,800 km, running from west to east, and up to 1,200 km from north to south. Sahara covers most of Mauritania, Western Sahara, Algeria, Libya, Egypt, Sudan, Chad, Niger and Mali, and touches Morocco and Tunisia.

Sahara is very dry but there is an annual rainfall in most regions, although just a few dozen millimetres.

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