Río de Oro (
Spanish for "
Gold River",
Arabic: وادي الذهب
wādī-að-ðahab, often transliterated as Oued Edhahab), is, with
Saguia el-Hamra, one of the two territories that formed the
Spanish province of
Spanish Sahara after 1969; it was originally taken as a Spanish colonial possession in the late 19th century. Its name seems to come from an east-west
river which was supposed to have run through it formerly. The river was thought to have largely dried out - a
wadi, as the name indicates - or have disappeared underground.