To make their Gran Reserva wines, Riscal use grapes from vines over 30 years old, from their own estate vineyards and bought in from associated local growers. Once the wine destined to become a Gran Reserva has been selected, following the coupage of the wines of the new vintage, it is put into American oak casks where it will age for between two and a half and three years. This is followed by a further minimum of three years bottle ageing before release for sale.