The Duero crosses a high, harsh plateau of Castile at around 800 metres: savage spring frosts, scorching days, cold nights. Tempranillo — here called tinto fino — answers the ordeal with thick skins and plateau acidity, giving a red darker, stricter and more tannic than Rioja: black plum, tobacco, iron.
One estate carried the region alone for a century. Vega Sicilia, founded in 1864, has made Spain's most celebrated wine here, ageing its Único longer than almost any red on earth. Yet the appellation itself dates only from 1982, launched with nine wineries — and it was Alejandro Fernández of Pesquera whose dense, pure Tempranillos showed the world in the 1980s what the plateau could do. Hundreds of bodegas have since followed onto the riverbanks.