Port wine (also known as vinho do Porto, Porto or usually simply port) is a Portuguese fortified wine produced with distilled grape spirits exclusively in the Douro Valley in the northern provinces of Portugal. It is typically a sweet, red wine, often served as a dessert wine, although it also comes in dry, semi-dry, and white varieties.
The Douro valley where port wine is produced was defined and established as a protected region, and the name Douro thus an official appellation, in 1756, making it the third oldest, after Chianti (1716) and Tokaj (1730). The reaches of the valley of the Douro River in northern Portugal have a microclimate that is optimal for cultivation of olives, almonds, and especially grapes important for making port wine. The region around Pinhão and São João da Pesqueira is considered to be the centre of port production, and is known for its picturesque quintas – estates clinging on to almost vertical slopes dropping down to the river.
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