Douro

The Douro is the largest river of the Iberian Peninsula by discharge. It rises at the Pico de Urbión, the highest summit of the Picos de Urbión, first flows through 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. The scenic Douro railway line runs close to the river. Adjacent areas produce port (a mildly fortified wine) and other agricultural produce. A small tributary of the river has the Côa Valley Paleolithic Art site which is considered important to the archaeological pre-historic patrimony, designated a UNESCO World Heritage Site. Within Spain, it flows through the middle of the autonomous community of Castile and León, with the basin spanning through the northern half of the Meseta Central.