Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Wadi Hanifa (Arabic: ) is a wadi or valley in the Nejd region in central Saudi Arabia. The valley runs for a length of 120 km (75 mi) from north to south, cutting through the city of Riyadh, the capital of Saudi Arabia. The valley takes its name from the ancient Arab tribe of Banu Hanifa, who were the principal tribe in the area in the at thd dawn of Islam, though in those days the valley was better known as al-Irdh (Arabic: ). A string of towns and villages lie along the valley, including Uyaynah, Jubaila, Irga, Diriyah, and Ha''ir.