EnvironmentNorth Africa

The Green Sahara

9,001 BCE – 3,501 BCE

The world's largest desert is savannah, with lakes and hippos

In depth

The cause was the slow wander of Earth's axis, which pushed the monsoon north and filled a Lake Chad larger than the Caspian. Rock art at Tassili and Gilf Kebir shows cattle, hunting and dancing. When the rains withdrew — probably faster than they arrived — people pressed towards the Nile and the few remaining oases. It is among the clearest lines we have from climate change to state formation.

For children

For several thousand years the Sahara was green. There were rivers, lakes and grass, and people painted hippos, elephants and swimming figures on the rocks. Then the rains turned away, and the desert returned.

Connects to

Farming along the Nile5,001 BCE
The pyramids of Giza2,561 BCE
The Holocene begins9,701 BCE

Part of Terra Saga — the story of Earth on a timeline. terrasaga.org