Rioja is the most famous, traditional and certainly one of the best wine growing regions of Spain, the wines enjoy global recognition. Rioja is also one of the nuclei of quality Spanish viticulture, because it was also from here that the first bottled wines of the Iberian Peninsula were exported in the mid-19th century. The area experienced an enormous transfer of know-how when, towards the end of the 19th century, many wine growers from Bordeaux left their vineyards on the Gironde, devastated by phylloxera, and emigrated to the region on the Ebro to produce wine here, where phylloxera had not yet caused any damage. What has remained from that time is the obligatory barrel ageing in small oak barrels for the top quality wines, especially for the Reserva and Gran Reserva quality levels. Today, about 19,000 winemakers cultivate about 63,000 hectares of vineyards, but many of them are purely growers who sell their grapes to the big houses like Marques de Caceres or Bodegas Berberana. The climate in the foothills of the Pyrenees, where the vineyards are located at 300 to 800 metres above sea level, is cool due to the Atlantic influence beyond the Pyrenean massif, but the mountain range also keeps rain off, so that very little precipitation falls. Rioja is divided into a total of three sub-regions: the high-altitude Alavesa, north of the Ebro River, and Rioja Alta, west of the capital Logroño, and the much lower altitude Rioja Baja. Soils range from alluvial to ferruginous clay soils to chalk clay. A total of seven grape varieties are permitted for the production of Rioja wines: three for white and four for red. Rioja usually consists of a blend of the approved varieties as well as the sub-regions to give the wines substance, complexity and power, but also colour. The additional designations such as Crianza, Reserva or Gran Reserva are decided by the duration of barrel and bottle ageing.