Glendullan is a Speyside single malt from the distillery of the same name founded in 1897. The distillery was owned by Macdonald, Greenless and Williams, and DCL (now Diageo). DCL built a second distillery with the same name in 1972. This is today generally bottled under the name Singleton of Glendullan to prevent confusion with the original distillery.

A Glendullan 26 year old distilled in 1978 and bottled at cask strength in 2005 for the Rare Malts series. Created in the mid-1990s by United Distillers (Diageo), the Rare Malts series features bottlings from many of the group’’s distilleries, including some of the lesser known whose production was generally used for blends, as well as closed distilleries such as Port Ellen and Brora. Bottled at cask strength, the whiskies in the range are also known for their sometimes astounding alcohol content, often exceeding 60% ABV. The Rare Malts range was discontinued in 2005.