Founded in 1881, Bunnahabhain (pronounced "BOO-na-HAven") Distillery is situated along the banks of the Sound of Islay in the Inner Herbidies archipelago. For over a generation, the distillery was only accessible by sea, and a large port, costing approximately £3,500 pounds at the time, was constructed in order to allow ships to unload barley and yeast near the distillery and load finished casks of whisky ready for sale. While technological improvements have made it easier to get to the distillery over the last century, little has changed in terms of Bunnahabhain's distillation process.

Bunnahabhain Single Malt Scotch Whisky is made from fresh Optic barley, which is lightly peated to approximately 3 phenol parts per million. Once the barley arrives at the distillery, it is milled and mashed with pure spring water drawn from the Margadale River. The water, which travels through an ancient bed of limestone, is transported by pipeline to the distillery and as a result, avoids travelling through the peatbogs of Islay.

Once the barley has been mashed, it is fermented in washbacks made of Oregon Pine for nearly three days. While wooden washbacks are more expensive and difficult to maintain as compared to stainless steel washbacks, they absorb a portion of the heat generated during the fermentation process and thus, create a lighter and more rich whisky. Following fermentation, the wash is distilled twice, first through Bunnahabhain's copper-pot wash still and again through its copper-pot spirit still. Then, the heads and tails of the distillate are removed by Robin Morton, Bunnahabhain's stillman (Morton began working at the distillery in 1978), before the whisky is allowed to mature at Bunnahabhain's warehouse. The sea-facing warehouse, which rests on the banks of the Sound of Islay, enjoys a cool, salty breeze that adds a touch of salt to the whisky as it ages. "Over the years, you get this slight salty taste," says Andrew Brown, Bunnahabhain's distillery manager. "The older the whisky gets, the saltier it becomes. It's not overpowering — it's just a hint."

Bunnahabhain 25 Year Old Single Malt Scotch Whisky is matured for a quarter-century in three unique types of casks: ex-bourbon (20%), ex-Scotch (60%) and ex-Oloroso sherry (20%). As a result, the whisky has a sweet caramel aroma, with hints of berries, vanilla cream, roasted almonds, malt and spice cake on the palate. The finish is soft yet dry, with touches of brown sugar, cloves and caramelized oranges.

The whisky earned the Double Gold Medal at the San Francisco World Spirits Competition in 2011, 2012 and 2013. In addition, the whisky was named the "Best Islay Single Malt"at the World Whiskies Awards in 2014.

Only a handful of bottles of this single malt exist.