Douro

The Douro (, , , ; ; ) is the largest river of the Iberian Peninsula by discharge. It rises near Duruelo de la Sierra in the Spanish province of Soria, meanders briefly south, then flows generally west through the northern part of the Meseta Central in Castile and León into northern Portugal. Its largest tributary (carrying more water than the Douro at their confluence) is the right-bank Esla. The Douro flows into the Atlantic Ocean at Porto, the second largest city of Portugal.