Dão is a Portuguese wine region situated in the Região Demarcada do Dão with the Dão-Lafões sub region of the Centro, Portugal. It is one of the oldest established wine regions in Portugal. Dão wine is produced in a mountainous region with a temperate climate, in the area of the Rio Mondego and Dão rivers in the north central region of Portugal. The region became a Denominação de Origem Controlada (DOC) appellation in 1990. The Dão region is the origin of the Touriga Nacional vine that is the principal component of Port wine.

The wine region is located primarily on a plateau that is sheltered on three sides by the granite mountain ranges of Serra da Estrela, Serra do Caramulo and Serra da Nave. This helps the area maintain its temperate climate away from the effects of the nearby Atlantic Ocean. The region experiences abundant rainfall in the winter months and long, warm dry summers leading up to harvest. The region's vineyards are planted on sandy well-drained soil on top of granite rock.

More Info: en.wikipedia.org