From Tupungato the route continues into the heart of the Valle de Uco. The valley, which runs through the three departments of Tupungato, Tunuyán, and San Carlos over roughly 70 kilometres of Andean foothills, is Argentina's most intensely planted high-altitude wine zone. Vines here grow between 900 and 1,500 metres (2,950 to 4,920 feet) above sea level, irrigated by meltwater from the Andean glaciers and dry-farmed under conditions of intense ultraviolet light, cool nights, and very little rain. The combination produces wines of uncommon concentration and freshness, particularly the Malbec that made the region famous, but increasingly also Cabernet Franc and Chardonnay. The modern era of the valley dates only to 1992, when Nicolás Catena Zapata planted the first designated vineyard in what had previously been a source of bulk grapes for blending — though Italian and Spanish immigrants had been farming vines here since at least the 1920s. Since then, investment has arrived from across Argentina and from France, Belgium, the United States, and further afield, and the valley now counts over 75 working bodegas.
The midday stop at Valle de Uco allows for a winery visit. Most bodegas here require advance reservations; a tasting with a guided cellar tour typically lasts around two hours and often includes a seated lunch or charcuterie pairing. Names worth noting in this northern subzone include Andeluna, Salentein, and Clos de los Siete; those pushing further south toward La Consulta and the Gualtallary subzone are working at the frontier of the valley's ambitions. The landscape around any of these estates is equally worth the visit: broad vineyard terraces, poplar windbreaks, and the unobstructed wall of the Cordillera behind.