Mortlach's main claim to fame is that it was the first of seven distilleries to be built in and around Dufftown. The distillery operates a uniques distillation process which distills the spirit 2 times. This, combined with the worm tubs used to condense the spirit, give the whisky the complexity for which it is renowned. This also makes the whisky suitable for longer ageing. Unlike most distilleries in Scotland, Mortlach was given permission to remain in production during most of World War II.