The following map shows some of the early cultures preceding the predynastic period. These cultures cross over modern imaginary barriers erected by Western scholars that supposedly prevent contact between Saharan and sub-Saharan Africa, and also between West and East Africa. For some reason there barriers seem to have been more of an obstacle to West to East and South to North movement than vice a versa. However, the actual evidence show that gene and culture flow in all directions dates from the earliest times and has continued at different rates over history. The earliest agricultural systems to enter into Egypt proper seem to have come from the Sahelian Aquatic culture and the southern Lupembam and related cultures. The latter seems to have penetrated to Wadi Halfa, near Abu Simbel, while the former reached considerably further north.

References

J. Desmond Clark (1970) The Prehistory of Africa, London.
G.S.P. Freeman-Grenville (1991) The New Atlas of African History, New York.
Hammond Incorporated (1987) Hammond Atlas of World History, Maplewood.
Jocelyn Murray (ed.) (1981) Cultural Atlas of Africa, New York.