Ahvâz

Ahvaz stands on the Karun River in the hot plain of Khuzestan, where the water breaks through a low ridge in a series of rapids. The city was an important centre of the medieval province, known for its sugar and the cultivated lands watered by the river. An ancient barrage and a great brick bridge once crossed the Karun, linking the districts on its banks. After the Mongol period the city declined, and authority in the region passed to the Musha'sha' and later the Safavids. The river nevertheless remained a valuable route through the plain. Its rapids interrupted navigation, obliging goods to be transferred between vessels travelling on the lower and upper reaches toward Shushtar.