The Douro Valley region of Portugal is one of the world's oldest wine-producing regions and is renowned for its production of high-quality fortified and unfortified wines. The region's climate is characterized by hot and dry summers and cold winters, with significant temperature variations between day and night.

The most famous wine produced in the Douro Valley is Port, a fortified wine made from a blend of grape varieties, including Touriga Nacional, Touriga Franca, Tinta Roriz, and Tinta Barroca. The grapes are grown on steep hillsides along the Douro River and are harvested by hand.

In addition to Port, the Douro Valley is also known for producing high-quality red and white table wines. The red wines are typically made from the same grape varieties used to produce Port and are full-bodied with intense flavors of dark fruit, spice, and chocolate. The white wines are made from grapes such as Viosinho, Rabigato, and Gouveio and are known for their crisp acidity and citrus flavors.