Wadi al-Rummah

Wadi al-Rummah or ar-Rummah with a length of almost 600 km (370 mi) is the largest seasonal Endorheic river, or wadi, in the Arabian Peninsula. Flowing for an estimated 60 days of the year, it is important for agriculture in a region considered the breadbasket of Saudi Arabia. The wadi originates near Medina at Jibāl al Abyaḑ (the White Mountain). It then runs northeast, joining several smaller wadis, including Mohalla Wadi and Murghala Wadi to the north and Jifn Wadi and Jarir Wadi to the south. It ends at the Thuayrat Dunes of the ad-Dahna Desert in Al-Qassim Province, near Buraidah. The wadi then sinks beneath the sand dunes and emerges on the other side of the desert as Wadi al-Batin (approx. 425 km (264 mi)), which continues towards the northeast and forms the western boundary of Kuwait. It empties into the Persian Gulf. The wadi is wide, for it was once a major river, possibly the modern location of the biblical Pishon. According to Dr. Abdullah Al-Musnad from the University of Qassim, about 10,000 years ago it was a perennial river flowing from Medina to the Persian Gulf, with a total length of 1,200 km (750 mi). Periods of drought, largely after the mid 1800s, and the movement of sand at Althwairat and Dahna cut the course of the valley into three parts: Wadi al-Rummah (the longest, at 600 km (370 mi)), Wadi Aloddi (45 km (28 mi)), and Wadi al-Bati

Flows through: Saudi Arabia.

River data from Wikidata (CC0); lengths normalised to a common unit.