Tuwaiq Mountains

The Tuwaiq escarpment forms a narrow plateau in Riyadh Region, from the Thuwayrat sands in Al-Zulfi through Al-Washm and Al-Arid to the edge of the Rub al Khali, rising up to 600 m above the surrounding plains. [1]

Its name, a diminutive of tawq (collar), reflects its ring-like shape. It has sheer western cliffs and a gentle eastern slope and is made of limestone with coral remains showing the area was once under water. [1]

Wadis descend from its eastern side, chief among them Wadi Hanifah. Settlement along its edges dates to prehistory, and pilgrim and trade caravans crossed it. On its slopes Saudi forces fought the Ottoman army in 1233 AH/1818 CE during the invasion of Diriyah, capital of the First Saudi State. [1]