🇪🇬 Egypt · Hydraulic works
Sadd el-Kafara – Wadi Garawi Old Kingdom Dam
Early Old Kingdom (Djoser–Sneferu) · Old Kingdom Egyptians (Memphite)
World's oldest dam (2650 BCE)—110-m Old Kingdom embankment diverting Wadi Garawi floods.
🇾🇪 Yemen · Hydraulic works
Marib Dam
Sabaean Kingdom, Early South Arabian (~1750 BCE – 570 CE) · Sabaean (South Arabian, Kingdom of Saba)
Earthfill diversion dam spanning the Wadi Adhanah and flanked by the limestone North and South Sluices with Sabaean monumental inscriptions.