Douro

A 1908 image of boats along the Douro River

The Latin name Durius was likely a Celtic name before overwhelming Romanization of both main Iberian languages. If so the Celtic root is *dubro- (in which family of languages the final vowel sound often changes with context, as in Latin).[5] In modern Welsh, dŵr is "water," which is cognate with dour in modern Breton, dobhar in Irish and gives rise to Dover on the Dour and the other modest rivers the Dever and Deveron (Dubh Èireann) in British Isles. In Roman times, the river was personified as a god, Durius.

A folk-etymological derivation suggests that the name comes from the Portuguese or Spanish for "golden".[6][7]

The drainage basin was depopulated in the 8th century. According to Claudio Sánchez-Albornoz this was a deliberate act by Alfonso I of Asturias for the defence of his Kingdom, which led the area to be named Repoblación.

The Douro vinhateiro (vine-land) of the Douro Valley in Portugal, long devoted to vineyards, has been designated by UNESCO as a World Heritage Site. The wine was taken downriver in flat-bottom boats called rabelos, to be stored in barrels in cellars in Vila Nova de Gaia, just across the river from Porto. Nowadays port is transported there in tanker trucks.

In the 1960s and 1970s, dams with locks were built along the river, allowing river traffic into the upper regions in Spain and along the border.

In 1998, Portugal and Spain signed the Albufeira Convention, an agreement on the sharing of trans-boundary rivers to include the Douro, Tagus and Guadiana. The convention superseded an agreement on the Douro, signed in 1927, that was expanded in 1964 and 1968 to include tributaries.[8]

A SPOT Satellite image of the Douro River

Profile of the Douro River, from its source in the mountains of the Sistema Ibérico to Foz do Douro

It is the third-longest river in the Iberian Peninsula after the Tagus and Ebro. Its total length is 897 kilometres (557 mi),[9] of which only sections of the Portuguese section, being below a fall/rapids line, are naturally navigable, by modest rivercraft.[10]

In its Spanish section, the Douro crosses the great Castilian meseta and meanders through five provinces of the autonomous community of Castile and León: Soria, Burgos, Valladolid, Zamora, and Salamanca, passing through the towns of Soria, Almazán, Aranda de Duero, Tordesillas, and Zamora.

The most important tributaries in this region are the Pisuerga, passing through Valladolid, and the Esla, which passes through Zamora. This region is generally semi-arid plains, with wheat and in some places, especially near Aranda de Duero, with vineyards, in the Ribera del Duero wine region. Sheep rearing is also still important.

The drainage basin borders those of Miño to the north, Ebro to the east, and Tajo to the south.[9][10]

For 112 kilometres (70 mi), the river forms part of the national border line between Spain and Portugal, in a region of narrow canyons. It formed a historical barrier to invasions, creating a cultural/linguistic divide. In these isolated areas, in which the Aldeadávila Dam impounds the river, there are protected areas: the International Douro Natural Park (on the Portuguese side) and the Arribes del Duero Natural Park (on the Zamoran margin).

The Douro fully enters Portuguese territory just after the confluence with the Águeda River; once the Douro enters Portugal, major population centres are less frequent along the river. Except for Porto and Vila Nova de Gaia at the river mouth, the only population centres of any note are Foz do Tua, Pinhão and Peso da Régua. Tributaries here are small, merging into the Douro along the canyons; the most important are Côa, Tua, Sabor, Corgo, Tavora, Paiva, Tâmega, and Sousa. None of these small, fast-flowing rivers is navigable.

Human geography

Aerial view of the Douro estuary, Porto

Major Spanish riverside towns include Soria, Almazán, Aranda de Duero, Tordesillas, Zamora and major Portuguese towns include Miranda do Douro, Foz Côa, Peso da Régua, Lamego, Vila Nova de Gaia, and Porto. The most populous cities along the Douro River are Valladolid and Zamora in Spain, and Porto and Vila Nova de Gaia in Portugal. The latter two are located at the mouth of the Douro at the Atlantic Ocean.

In Portugal, the Douro flows through the districts of Bragança, Guarda, Viseu, Vila Real, Aveiro and Porto. Porto is the main hub city in northern Portugal. Its historic centre has been designated as a UNESCO World Heritage Site because of its significant architecture and history.

The Ribeira (meaning riverside). Its tall, colourful-building terraces is the main part of the river bank in the major city of Porto; it attracts numerous tourists

These reaches of the Douro have a microclimate allowing for cultivation of olives, almonds, and especially grapes, which are important for making port. The region around Pinhão and São João da Pesqueira is considered to be the centre of port, with its quintas (or farms/estates) that extend along the steep slopes of the river valleys. In the 21st century, many of these are owned by multinational, reputed wine companies.

Recently, a prosperous tourist industry has developed based on river excursions from Porto to points along the Upper Douro valley.

The Douro railway line (Linha do Douro) was completed in 1887; it connects Porto, Rio Tinto, Ermesinde, Valongo, Paredes, Penafiel, Livração, Marco de Canaveses, Régua, Tua and Pocinho.

Pocinho is near the very small city of Foz Côa, which is close to Côa Valley Paleolithic Art site. This is considered important to the archaeological pre-historic patrimony, and it has been designated as a UNESCO World Heritage Site.

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  The Douro in Zamora (Spain)
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  The Pisuerga River (tributary to the Duero) in Valladolid
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  The Upper Douro valley where Port wine grapes grow
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  The typical rabelo boat and Porto historical district in background
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  Port wine signs by the Douro River
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  Panoramic view of Oporto
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  The river between Porto and Vila Nova de Gaia
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  The river near Régua, Portugal
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  Douro Internacional near Miranda do Douro
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  Arribes del Duero near Aldeadávila
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  The river mouth in Porto
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  Over Porto
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  Douro Estuary
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  Looking across the river mouth from Foz do Douro to Vila Nova de Gaia (Atlantic Ocean on the right)
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  Typical almond tree, mostly seen along the river in Portugal

• List of rivers of Portugal
• List of rivers of Spain

• DouroValley.eu Main tourism website
• IPTM – Instituto Portuário e dos Transportes Marítimos, Delegação do Norte e Douro
• Rio Douro Sound Map