Which Portuguese wine region is famous for producing port wine?

The Portuguese wine region famous for producing port wine is the Douro Valley.

The Douro is centered on the Douro River in northern Portugal, where steep, terraced vineyards grow in a hot, dry continental climate sheltered by mountains. Grapes are harvested there for port, a fortified wine whose fermentation is stopped by adding aguardente, a neutral grape spirit. This preserves sweetness and raises the alcohol level.

The region’s formal boundaries were established in 1756 under the Marquis of Pombal, making it one of the world’s oldest demarcated wine regions. The wine takes its name from Porto, the coastal city where it was historically stored and exported, not from the place where its grapes are primarily grown.

A common mix-up is choosing Porto as the region. Porto is the port city and commercial gateway; the vineyards lie inland in the Douro Valley. The Douro also produces substantial quantities of unfortified table wine.