For spirit to qualify for the title of Scotch whisky, it must be matured for at least three years in an oak cask, in Scotland. This allows mellowing and development of flavour and colour to take place.
Originally, the distillery warehouses were constructed with an earth floor at ground level and upper timber floors. These warehouses have long gone with the exception of No. 1 Warehouse, which is over 100 years old and still uses the orginal storage methods, and has been retained for long term storage (8 years or more) of whisky.