At A.D. Rattray, they go to great lengths to source interesting and unusual casks which reflect the different styles and nuances of the 6 Scotch whisky regions. These are bottled at their natural strength and colour and without chill-filtration so that all of the wonderful flavours which have developed over years spent in the casks are retained. This 25 Year old Highlander was distilled back in 1991 and filled in a bourbon hogshead.