Trás-os-Montes ("behind the mountains") is a Portuguese DOC (Denominação de Origem Controlada) with the same borders as the Transmontano Vinho Regional zone within the Tras-os-Montes e Alto Douro administrative province in the far northeastern corner of Portugal.
The mountains cast a large rain shadow over Transmontano and a wide strip of western Spain beyond. This makes the area one of Portugal's driest. Consequently the best vineyards to qualify for the DOC follow the paths of the region's four main rivers: the Douro, the Sabor, the Tua and the Tamega. Soils are mostly schist with some areas tending toward granite or chalk.
Trás-os-Montes vineyards sit at varying altitudes and as a result produce various wine styles. Vineyards located in cooler, higher areas typically produce wines that are lighter in body and lower in alcohol, while the lower-lying areas are the source of fuller-bodied wines that are often perceptibly high in alcohol. Some of the higher vineyards in the region supply grapes for Portugal's most famous wine, the semi-sweet, lightly sparkling rosé, Mateus.
There are four subregions, classified as IPRs (Indicação de Proveniência Regulemtada); Chaves in the west is known for firm, dry red wines, while Planalto Mirandès in the east and Varosa produce light red wines and crisp, fresh, sometimes slightly sparkling white wines. Valpaços also produces light fruity reds often drunk with a local cake called Folar.
A wide selection of indigenous and international red and white grape varieties are grown and permitted within the DOC. Among the main local varieties are Boal Branco and Malvasia Fina (the naming of these seems interchangable in the region) Côdiga do Larinho, Síria, Tinta Roriz (Tempranillo), Touriga Franca, Touriga Nacional and Trincadeira.
