Tuwayq

(also Jabal Tuwayq), a mountain ridge in the central part of the Arabian Peninsula, in Saudi Arabia. Shaped like an arched cuesta, with a bulge toward the east, Tuwayq is approximately 1,000 km long and rises to an elevation of 1,143 m; the relative elevations above the adjacent plains range from 300 to 500 m. Tuwayq is composed primarily of limestones; karst is developed. The ridge is cut by the valleys of wadis. The grass and shrub vegetation is sparse, and oases are few.