Cardhu Distillery was originally known as Cardow. The place where it is located has also been known by variations of the same name. It is now Cardhu but was known in the past as Cardow and Cardoor. It gets its name from the Gaelic word for 'black rock'. The hamlet and the distillery are located in the heart of whisky country – Speyside. The distillery is built along the Knockando River.
A local farmer John Cumming used to distill alcohol illegally on his farm with his home grown barley and peat. He became a legitimate distiller in 1824. Actually this original distillery is not the one that exists today. The present Cardhu Distillery has the distinction of being started at the present site in 1884 by John Cumming's daughter-in-law, Elizabeth. She took over the management of the distillery in 1876 and built this new distillery near their farm. She also happened to sell the old stills to a certain William Grant who was about to start his own distillery, Glenfiddich.
Water for the distillery comes from the Mannoch Hill through two miles of pipe. Cardhu Distillery was extended in 1887 and was purchased by John Walker & Sons in 1893. Cardhu whisky has been a part of their blends, Johnnie Walker ever since. John Walker merged with DCL in 1925, with the distillery being extended in 1897 and rebuilt in 1961. The number of stills was increased from four to six. The name was officially changed from Cardow to Cardhu around 1980. It is now owned by UD and is part of the Diageo group.
About 30% of the production is sold as single malt; the remaining is used in various blends. Cardhu is the basis of the Johnnie Walkers blends, Red, Black, Green and Blue labels. The Cardhu single malt is sold in a bottle with an unusual shape, unlike most other single malts.
In 2003 the distillery released a whisky labeled Cardhu Pure Malt in the same bottle and label style. This led to a great controversy about pure malt and single malt as the new drink was actually a blend from various distilleries. A whisky bears the name of its distillery only if it is single malt. The original whisky was reintroduced after withdrawing the blend.