The Dao region is located in Beira, central northern Portugal, flanked by the mountain chains of Caramulo, Montemuro, Bueaco and Estrela, which offer protection from the prevailing winds. Within this basin configuration, there is a wide range of micro-climates strongly influenced by relatively steep valleys carved out by the Mondego, Alva and Dao Rivers and their numerous tributaries. The vineyards range from 200 to 700 metres above sea level. The warmest, driest plots lie within a triangular plateau between the towns of Viseu, Mangualde and Nelas, in which the late-ripening Touriga Nacional flourishes. The wide diurnal temperature shifts of up to 20°C, ensure the fruit is endowed with ample natural acidity. The soils are granite dominated sands, with particles of feldspar, quartz and mica which sparkle in the vineyards. They are lean, free-draining and relatively infertile soils, which force the vines to struggle, resulting in complex wines. The vines are cultivated sustainably and are pruned according to double cordon, simple cordon or Guyot, with the method tailored to control the vigour to ensure the best quality. The grapes are manually harvested.