Ribera del Duero sits at nearly 3,000 feet above sea level on Spain's central plateau, and that elevation, combined with a dramatic continental climate and the Tempranillo-based grape called Tinto Fino, produces wines of extraordinary concentration and structure. Today's episode covers the geography of Ribera, why the extreme diurnal temperature variation is the key to its character, its legendary flagship Vega Sicilia, and the producers who have built its modern reputation.