Nine thousand years before our era, summer monsoons coming from central Africa watered Upper Egypt and temporary laked formed. The Nabta Playa depression, whose area is close to 70 km², is one of them. Within this depression were discovered gazelles, hares, jackals, small mammals and cattle remains dating from eight thousand years before our era. These are traces of a seasonal occupation by the shepherds and their droves. About two thousand years later, small communities settled there, as the vestiges of a small village made up with eighteen houses, large and deep wells, places of worship made up with several cattle bones, testify.

The Nabta-Playa megaliths.

Within deposits dating from the fifth millenium before our era were otherwise discovered megalithic alignments and stone circles directed towards the solsticial or cardinal points - in other words, towards the rising or setting position of the Sun on spring or autumn equinox or summer or winter solstice (1). These certainly are the very first traces of stargazing, which may lie within a ceremonial even a funerary scope, and will have to be dealt in a deeper way through the use of the software leading to determine the astronomical source of orientation of any monument. Any of these informations suggest the early development of complex neolithic societies. Starting from the fourth millenia before our era, that is to say, from this epoch at which the climate became hyperarid again, these nomadic societies would take part in the birth of the Egyptian civilization.