The Portuguese DOC area for red and white wines was already defined by law in 1908. The huge area comprises 60,000 hectares of vineyards in the districts of Braga, Porto and Viana do Castelo. It stretches 130 kilometres long and 70 kilometres wide in the north-west of Portugal between the Douro and Minho rivers, which form the border with Spain. The entire area is also classified as Vinho Regional (VR) for Rios do Minho country wines. The cool climate, with an average of 2000 mm of rainfall per year, is very much influenced by the nearby Atlantic Ocean. The area is divided into six subzones Amarante, Basto, Braga, Lima, Moncáo (considered the best) and Penafiel, which differ in the grape varieties grown. However, the subzone is usually not indicated on the bottle label. The vines are raised in a pergola-like foliage system (tendone). This is where about a quarter of Portugal's wine is produced. However, about 60% is produced as simple, unbottled draught wines that resemble cloudy cider. The vineyards are cultivated by about 30,000 winegrowers with very small vineyards, often on a sideline basis.
Vinho Verde means "green wine," but this refers not to the color (there are white, rosé and red varieties), but to the fresh taste, the green landscape and the fact that the wine is made from grapes that are still green. The cool climate, the training and the special grape varieties produce must with little sugar and high malic acid content. The grapes, which are rather unripe due to early harvesting, are fermented only briefly. In former times a malolactic fermentation took place afterwards, today mostly carbonic acid is added. This results in a wine that is rich in acidity, fresh and sparkling. A vintage appears rather rarely. Most wines have only 9 to 10% alcohol by volume and should be drunk young. Because of its freshness and low alcohol content, Vinho Verde is called "summer wine". Only the Alvarinho wines from Moncáo are allowed to have more than 11.5%, all others are only declared as Rios do Minho.