César Fernández Díaz grew up helping his mother's family in the traditional underground cellars of Aranda de Duero, where wine was kept for household use and sold to friends and neighbors. He studied viticulture and oenology in Madrid and spent nearly a decade training with the most important figures in new Spanish wine: Bodegas Bernabeleva, Viña Mein in Ribeiro, and above all Comando G in the Sierra de Gredos — the project that most shaped his approach, with its emphasis on freshness, tension, and terroir transparency.

In 2018 he launched his own project with barely 1,800 bottles. He works fewer than 3 hectares spread across both banks of the Duero: in Fuentelcésped, on the south bank, where his family vines grow in sandy loam soils with quartzite gravels — vines of 70 to 100 years; and in Peñaranda de Duero, on the north bank, on clay-limestone at 870 metres with old certified-organic vines. His wines are bottled as Vino de la Tierra de Castilla y León by choice: the variety blends he works with — Tempranillo, Bobal, Bastardo, Listán Prieto, Albillo Mayor, Garnacha — fall outside DO regulations, and in any case he has no interest in conforming to the Tempranillo monoculture the appellation demands.

In the cellar he follows the Gredos school closely: indigenous yeasts, light extraction, neutral oak as a vessel with no stylistic role, and zero additions — unfiltered, unfined, no added sulfur. Carremolino comes from his oldest plot, with pre-phylloxera vines alongside others planted between 1915 and 1917, co-planted exactly as they were a century ago. Wine Advocate awarded it 95 points. The Espantaburros Clarete, a co-fermentation of red and white grapes in the traditional Castilian style, received 93 points. "Espantaburros" is the popular name of a wild scrub plant that grows across the dry fields of the area, one that — according to local tradition — used to startle the working donkeys.