The Douro Valley

 
In 1756 the Douro Valley became the first classic wine region to be legally demarcated.  Its vineyards were comprehensively classified the following year, almost a century before those of Bordeaux.
 
Cut off from the temperate coastal area by the Marão mountains, which shield it from the rain-laden winds blowing off the Atlantic, the Douro Valley has a climate of hot dry summers and severe winters.  Its wild and mountainous landscape is dramatic in scale and until relatively recently much of the region was remote and inaccessible.
 
Most of the finest vineyards are planted on the steep hillsides bordering the Douro River and its tributaries, such as the Pinhão, the Távora and the Rio Torto. About two thirds of the vineyard area is planted on slopes with a gradient of over 30% and the Douro Valley is the only significant wine producing area in the world to practice hot climate hillside viticulture.