There was no white 1925 Castillo at the winery and they even had doubts about whether the wine had ever been produced. To this, I showed them a bottle I shared with the owner or Rekondo restaurant in San Sebastián in June 2015. So it exists, but the winery does not keep any bottles. They were kind enough to uncork the white 1925 Reserva, from the year the Rioja appellation was created; it was a very good vintage in which some outstanding wines were produced, among them the red version of Castillo de Ygay or the Marqués de Riscal—both of which can still be found if you look hard enough. This 1925 is an amazing wine with aromas of smoked peat that made me think of an Islay single malt, white chocolate, notes of wax and old furniture, eucalyptus, figs... This does not quite reach the complexity and depth of the best vintages from the Castillo, but it's not that far off. This is simply superb. Sometimes some old whites from Rioja can feel too lean and sharp, and lack a bit in the middle; I think the challenge is to fill the palate and at age 90 (yes, once you write it, it's hard to believe it) this wine does it. The bottle I tasted had been recorked in 1988. There is no technical info about the production, ageing or sale of this wine, but the remaining wine in the bottle after the tasting was analyzed and revealed a wine with 12.28% alcohol and a pH of 3.05, with 6.82 grams of acidity (tartaric), 0.81 grams of volatile acidity and 113 milligrams of sulfur.