Sadd el-Kafara

Sadd el-Kafara was a masonry embankment dam on Wadi al-Garawi 10 km southeast of Helwan in Cairo Governorate, Egypt. The dam was built in the first half of the third millennium BC by the ancient Egyptians for flood control and is the oldest dam of such size in the world. Never completed, the dam was under construction for 10-12 years before being destroyed by a flood.