From Tuwaiq to the sands
Wadi Hanifah descends from the eastern side of the Tuwaiq range and begins west of al-Uyaynah. It runs from north to south-east with an average slope of 2.8 m, until it spills into the sands of as-Sahba village in al-Kharj Governorate.
Forty valleys feed it, the best known being Wadi Laha and Wadi Laban. The capitals of the first and second Saudi states, Diriyah and then Riyadh, both rose on its lands.
A green corridor
Its rehabilitation was overseen by what was then the High Commission for the Development of ar-Riyadh. Six open parks now line its banks, planted with tamarisk and acacia, and a weir-based biological treatment plant aerates the water to raise its oxygen levels.
Within Diriyah Governorate the wadi is the most prominent natural landmark, and the old capital still rises from its banks. Cities have since been built along its banks, and the wadi remains the most significant natural drain for water in Riyadh.