The Solera aging method used for Citadelle is a very intensive process of putting Citadelle into different type casks for anywhere from 2 to 5 months and will include American oak cask (to impart a touch of vanilla sweetness) and casks that once held Pineau de Charente (for a full-bodied, flowery roundness) and also Brandy (which imparts elegance). Once the gin has spent some time in casks, a portion of the gin from each cask will be moved into a large vat for blending, and new gin will be added to the remaining gin in the cask. Again, after aging for a specified period, the process of taking some of the aged gin out to be blended and adding new to the casks starts all over again. This is how the Solera process works.