The Saharan Mega-Lakes during the Holocene Wet Phase
Between c. 11000 – 3000 BCE, the Sahara was far from the desert it is today. It was covered in grassland and dotted with shallow lakes. Ancient humans used their waterways to travel up through Africa. Its legacy remains today in rock art and dried riverbeds.
Reddit user dontfearme22 made a map of speculative reconstruction of this lost world.
The humid African period started to a widespread settlement of the Sahara and the Arabian Deserts and profoundly influenced African cultures, such as the origin of the Pharaonic civilization.
The humid African period ended about five thousand years ago during the Piora Oscillation cold period. At the same time, some data pointed to an end 5.5 thousand years ago, in the Sahel, Arabia, and East Africa.