Remains of houses and tombs stone have been found dating back to the Neolithic Age (4000 BC) in the Helwan District of Egypt (Raas El Houf and El Maasara areas).
2700 - 2600 BC
During the Old kingdom period when the pyramids when built, the Sadd-el-Kafara dam was constructed in a valley, probably to control floods. Having lasted 10-15 years to construct the dam was destroyed by a flood before its completion, and abandoned for thousands of years.
The dam was discovered by the German archaeologist G. Schweinfurth. It is considered the oldest large scale dam in the world.
Today to a large extend the dam is not appreciated as an important archaeological site.