In recent years the number of fans of fortified wines has grown considerably. The Portugal, with particular reference to the wine-growing area near the Douro river, stands out for the production of one of the most particular and complex wines in the world, namely the Liqueur Harbor. Like all fortified wines, the Port is also subject to a specific oenological technique. In fact, generally during fermentation, a certain quantity of alcohol is added, just to determine the alcohol content and to complete the fortification. The valley of the Douro, destination of many tourists everywhere, is one of the most important wine growing areas in the world. This Mediterranean area stands out for its extraordinary beauty, for the unchanged plant techniques and dating back to Roman times. The valle del Douro is also the area where the first control and quality systems of the territory were introduced. The harvest, even today, is performed manually and the spontaneous fermentation is blocked through the described fortification process. For a period between 3 and 50 years, the Port is kept in the traditional pipas. There are several types of Port wine: white, rosé, tawny, pink and ruby. In addition, there are special categories, which differ essentially for the period of aging in the pipas. The Porto Vintage made from differently de-vegored grapes is particularly prized. Equally prestigious is the Porto Single Quinta, so called because it is produced exclusively with grapes that come from a single estate.