The Douro River
Douro (or Duero)River, a river of Portugal and Spain. (Douro is Portuguese; Duero is Spanish.) Its source is in the Old Castile region of north-central Spain. The river flows westward through the León region of Spain. It turns south-westward and follows the Spanish-Portuguese border for about 70 miles (110 km), then crosses westward through northern Portugal, to the Atlantic near Oporto. The river's total length is 485 miles (781 km); it drains an area of 30,500 square miles (79,000 km2). The river is important chiefly for irrigation and as a source of hydroelectric power.