The Sahara Desert is almost the size of the United States.
Why it is true
The Sahara covers about 9.2 million square kilometres, while the United States has approximately 9.8 million. Despite being a desert, the Sahara was once a green region with lakes and rivers thousands of years ago, as fossils and cave paintings show.
Source: National Geographic
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Related facts
The Sahara was a tropical ocean 50 million years ago.
The Namib Desert in Africa is the oldest desert in the world, having existed for at least 55 million years.
The Sahara desert is not mostly made of sand, but rather gravel and rock.
The Atacama Desert is the driest non-polar place on Earth.
