Could the river Duero become the backbone of a communication strategy for the wines of Castilla y León as it is the case of the Garonne, the Mosel or the Rhône?
Judging by the presentations at Duero International Wine Fest, held in Burgos earlier this month, the river vertebrates most of the wine regions in Spain’s largest autonomous region, even if some of them, such as Bierzo in León (which is part of the Miño basin and plateau) and Sierra de Salamanca and Cebreros in Spain’s Central moun-tain range (on the river Tagus), lie outside its area of influence.
This article is a summary of my presentation at the conference, delivered alongside Fernando Mora MW, in which we set to include the Duero among the great wine ri-vers of the world. Mora used four examples to expose the way a river can shape a wine producing area and highlighted the benefits, sometimes very contrasting, based on the climates, latitudes and the landscape. For my part, I focused on the Duero trying to identify similarities and differences with other wine rivers.
Stating the obvious is usually a good start. Mora reminded the audience that “a river is a large natural stream of water flowing in a channel to the sea, a lake, or another river.” Wine regions have distinct characteristics according to where they are located. Mountains or high elevations are located on the upper course of the river, where water shows its power of erosion; that’s why valleys are usually V-shaped and have steep slopes. Eroded materials are dragged to the middle course where the relief is usually flater to finally settle on the lower course of the river.
The main obvious element that a river brings to any wine region is the erosion as it shapes the landscape. According to Fernando Mora MW, other key factors include a moderating effect on the climate, the reflection of the sunlight, generating day-night thermal variations that contribute to balance ripeness, its role as a gateway for different atmospheric phenomena, the way in which rivers attract population settlements and their role as means of transport.
There are also negative factors: unsuitable exposures for grape growing; humidity can cause diseases in the vine; fertile soils may lead to excessive vigour; and the cost of land may be particularly high in rivers near populated areas.
In this complex framework, producers should look for optimal areas where the climate and terrain are able to create the conditions (see Photo 2) in which sugar, acidity, tannins, aromas and flavours are balanced.
Using four examples, Fernando Mora MW explained the different ways in which a river can shape the landscape of a wine producing region and influence, therefore, the style of its wines. In each case, he used a catchy descriptor to capture the spirit of each of them.
Bordeaux and the Garonne, an aristocratic river. Even if its wines were known in England since 1152 when Bordeaux was under English rule, it was the Dutch who developed the wine trade in the 18th century and drained and planted the Médoc with vineyards. The famous 1855 classification that listed producers according to their reputation and wine prices was the first step towards aristocracy. Other milestones include the mis en bouteille à la proprieté by Mouton-Rothschild (1950s), the en primeur sales since the 1970s, Parker's influence since the 1982 vintage or soaring prices and demand in the early 2000s.
The landscape is shaped by the confluence of the Garonne and Dordogne rivers in the vast Gironde estuary. Quality factors are linked to the warm Gulf Stream, the protection offered by one of Europe’s largest mass of pine forests and the thermal stability provided by the estuary. This is Atlantic climate with high levels of rainfall and marked differences between the left and right banks. On the left bank, the best vineyards are located in Haut Médoc and Péssac-Léognan and feature well-drained gravelly soils. Dominated by limestone and clay, the stars of the right bank are St.-Émilion and Pomerol.
The Rhône, a hippy river. The moniker is unlikely to have pleased the Popes who ruled in Avignon in the 14th century, but it does reflect the current effervescence in an area that clearly favours low-intervention wines. One of the oldest wine regions in France, the Greeks started farming the north and the Romans continued their work in the south. Hermitage wines reached great fame among the English between the 17th and the 19th centuries and it was standard practice to blend them with weaker Bordeaux reds to add structure. Châteauneuf-du-Pape was France’s first AOC in 1936.
The landscape varies abruptly between the upper course of the river (Northern Rhône) and the middle course to the south (Châteauneuf-du-Pape). In the north, vines grow on steep slopes that maximize solar exposure. The best locations are found on the right bank on granite and slate soils; erosion is a constant threat. The climate is continental, with abundant rainfall (900mm). The south, however, is Mediterranean. Vines grow on plains and hills with alluvial soils -particularly notable are the so-called galets, large stones that retain the heat of the sun. There are many more hours of sunshine, less rainfall (700 mm) and the marked influence of the Mistral wind.
Mosel, a monastic river. Germany’s wine jewel is one of the most ancient wine regions of the world; monastic orders played a key role in the development of grape growing. More importantly, the first vineyard classification, which dates back to 1680, had a direct effect on wine taxes: 30 thalers for a 960-litre foudre from the Upper Mosel compared to 15 thalers for the same amount of wine produced in the Lower Mosel.
A tributary to the Rhine, the river zigzags between dizzying slopes. It plays a key role in ripening grapes in an extremely cold and humid area with average temperatures that are 8ºC below what’s needed to make quality wines. Aside from the effect of the Mosel on the temperature regulation, other key elements of this area are the protection of the mountains and the blue slate soils, capable of absorbing the heat. Despite these benefits, southern exposures are still needed to obtain great grapes.
Napa, a nouveau riche region with a river. After suffering the effects of Prohibition (1920-1933), Napa’s renaissance officially started in 1966 when Robert Mondavi set up what is considered the first modern winery in the region. The partnership between American and European investors and the introduction of Old World winemaking methods eventually brought prosperity to the area. In the 2000s, Napa’s best Cabernets rivalled Bordeaux’s grand crus.
However, very few wine lovers are aware of the existence of the Napa river and the favourable conditions it creates for wine growing. Beyond the moderating effect on the temperature due to the influence of the Pacific, the river offers the perfect entry gate for fog: a funnel-shaped valley, stretching five miles wide on the estuary to just one mile inland. As a result, the southernmost areas are covered with fog almost all day and are the coolest, while inland regions further north are fog-free, fail to benefit from the influence of San Pablo Bay, and are therefore warmer. It’s striking to have three Winkler climatic areas (I, II and III) in a relatively small territory. The fertile banks of the river, on the other hand, are destined to high-yielding varieties like Sauvignon Blanc.
The Duero basin is the largest in the Iberian Peninsula, and its area of influence expands across most of the northwest. The river is born in the Picos de Urbión mountains in Soria (Castilla y León) at over 2,000 meters of altitude and flows down to the Atlantic ocean in Porto (Portugal). 572 of its close to 900 kilometres in length run through Spanish territory with 112 additional km creating a natural border between Spain and Portugal.
The Spanish wine regions influenced by the Duero are located in the middle course of the river and stand at an elevation of 600 to 850 metres, although vines grow up to 1,000 metres in some parts of Ribera del Duero. The border marks a sudden drop in altitude in the Arribes region with subsequent changes in the landscape: the valley narrows and turns into breathtaking gorges and ridges. The elevation is notably lower on the Tras-os-Montes and Douro regions in Portugal, where the Atlantic influence is clearly evident. Except for the bordering region of Arribes, the climate in Spain’s Duero regions has a strong continental influence that can be really extreme in the easternmost area of the valley. Close to 90% of the Duero basin suffers from summer droughts.
In terms of wine grapes, the Duero is mainly about Tempranillo in its Spanish section. It is the dominant variety in all regions marked with red and garnet colours (see the map shown in Photo 3 on the slider above by illustrator Luis M. Munilla). The yellow patch in the centre is Rueda, where white grapes, particularly Verdejo, are dominant. Both Tempranillo and Verdejo have stepped beyond their traditional growing areas to become Spain’s two flagship varieties.
Prieto Picudo rules in Tierra de León (coloured green on the map) and to the south in Valles de Benavente (Zamora) where it is grown alongside Tempranillo. Arribes has its own, extremely rich grape universe but it has more in common with Portugal than with Spain.
In his work Vignobles et vins du Nord-Ouest de l'Espagne, French geographer and historian Alain Huetz de Lemps rejects the idea of a plateau to explain the geography of the Douro basin. Huetz de Lemps, who spent 10 years travelling from Rioja to Galicia across the Iberian Peninsula and poured over countless archives and documentary sources, described it as a sedimentary basin with tertiary deposits, thus involving a varied and complex geology. Photo 4 shows the original map published in his book including several districts named after their main crops —Tierra del Pan (Land of Bread), Tierra del Vino (Land of Wine) or Tierra de Pinares (Land of Pine Forests).
Bread, wine and wool were the pillars of development in the villages of Castilla y León. Current Duero vineyards are the result of the Reconquista against the Moors and the repopulation of abandoned, destroyed land that for decades was the scene of battles or scorched earth tactics. Wine was a crucial part in the diet of the new settlers (from Galicia, Asturias, Cantabria and Basque Country) who moved there from the North.
Sales to the north indicate that Toro was the first commercial vineyard in the Middle Ages. Its wines are mentioned in Libro del Buen Amor, written by the Archpriest of Hita in the 14th century, and are known to have travelled to America. Under the growing power of Castile, particularly during the 16th century, and of its prosperous cities (Burgos, Salamanca and Valladolid, which was the capital of the kingdom between 1601 and 1606, exceeded 20,000 inhabitants) other wine styles appeared. The high-alcohol, rich whites of Tierra de Medina and the “claretes” (traditional rosés) made from Aranda to Peñafiel in the current Ribera del Duero region were the most notable.
The northern coast proved a natural market for the wines of Castilla y León until the 19th century. After phylloxera, the arrival of the railway and a renewed road network set the decline of the Duero, as Castilla y León wines were replaced by the more competitive wines from La Mancha and southeastern Spain. Its renaissance began with the modern development of the wine appellation system in Spain, particularly active since the 1980s.
The river Douro, as in most of the examples cited by Fernando Mora MW, brings life and shapes the landscape helping to create a great diversity of soils. Image 5, with cross-sections of three different places in Ribera del Duero (more information about the area here) shows the impact of elevation and how different widths in the valley create varying soil outcrops that are reached by vine roots.
Marked differences between day and night temperatures are a crucial quality factor in most regions of Castilla y Léon resulting in wines with the required balance and structure to make them suitable for ageing.
The fact that the Duero is not navigable on the Spanish side is an obvious weakness. One only has to look at the way the Douro contributed to the development of an entire region in Portugal as wines were sent downstream to age in Vilanova de Gaia and subsequently shipped to different destinations.
Climate-wise, continentality can be extreme so the risk of frost extends beyond spring into the early autumn, just before the harvest. This constant threat illustrates the area’s harsh conditions which are echoed by the austere moor-rich landscape with isolated hills crowned by spectacular castles built after the Reconquista. This scenery has undoubtedly forged the character of the people living and working on the banks of the river Duero and its tributaries.
The elevation is a major difference with other European wine rivers and it compensates for the lower latitude providing wine regions in the Duero with tools against climate change both in terms of growing grapes and cooler orientations.
Diversity is the key word to describe the wine regions of the Duero in its Spanish sector. There are myriad soils and exposures and countless areas waiting to be explored in this vast part of the country -Covarrubias in Arlanza, pre-phylloxera vines grown on sandy soils in the province of Segovia, in the DO Rueda; high altitude old vineyards in Soria (Ribera del Duero) or Arribes, a remote and rustic territory with an amazing wealth of grape varieties showing great potential. To some extent, other regions outside the Duero basin are also perceived as remote but are nevertheless a source of diversity.
In terms of styles, the area is slowly recovering some traditional wines -there is a residual niche of white wines in Ribera del Duero which remain outside of the appellation; Dorado styles from Rueda are making a comeback and “claretes”, the area’s traditional rosés are waiting for their chance to shine internationally in the rosé category. The future may bring an opportunity for local grapes such as red Prieto Picudo or white Albarín from León, as well as Bruñal and Juan García in Arribes.
The recovery of minor grape varieties carried out by Itacyl (Castilla y Léon’s Agrotech Institute) opens up a wealth of opportunities and alternatives for producers to make fresh reds with less structure and to offset Tempranillo’s naturally high pH. More information on this subject will soon be published on SWL.
For Fernando Mora MW, rivers can make wine regions shine in many different ways: the Garonne is a story of soils and commercial success; the Rhône boasts a long history and a unique topography; the Mosel is all about exposures and early classifications; and Napa stands out for its economic power and its unique location. The Duero could shine for the complexity of its soils and the diversity of wine styles and grape varieties. If that were to happen, it could well be called the plural river.