Single malt Scotches are made all over Scotland and are grouped together by region. Traditionally, there were four regions: The Highlands, Lowland, Islay, and Campbeltown. Speyside is a newly established region, splitting away from The Highlands and sporting over half the distilleries in Scotland. Campbeltown lost its status as an official Scotch region a few years ago, but has been reinstated recently.
Each region has it’s own distinct style and flavor, which mainly comes from the ingredients used. It’s a subtle difference, but that’s why you drink single malt scotch: for the nuanced and subtle flavors.
Scotches distilled in the Lowland region tend to have a maltier, less peaty flavor which makes for a more subdued whisky. Traditionally, distillers in the Lowland region also triple distill their whisky, which further mellows the flavor. As geographically large as the Lowland region is, there are relatively few distilleries here. Notwithstanding, Lowland Scotches are some of the more demanded and pricier Scotches around the world.
With the increased number of distilleries in the Speyside sub-region, they were given full region status by the Scotch Whisky Association. More than likely, the single malt at your neighborhood bar (if they even have one) is from this region. Speyside Scotch is the most famous of the Scotches: Cragganmore, Glenfiddich, The Glenlivet, Glen Moray, The Macallan are all from Speyside. This whisky tends to be sweeter than the other regions, likely because of the practice of aging the whisky in sherry barrels. If there is any peaty character to any of these Scotches, it is only a hint.
A significantly large portion of Scotland, the Highland region produces robust, full-bodied Scotch. They commonly have a floral, spicy flavor that can be attributed to the regional peat soil used in the malting process.
Campbeltown is a tiny peninsula that used to support over 30 distilleries and was lauded as the Whisky Capital of the World. There are only 3 Campbeltown distilleries left: Glen Scotia, Springbank, and newcomer Glengyle. Campbeltown whiskys have a mix of sweet and salty flavors, and tend to be smokier than other Scotches.
The most distinct of the single malts, Islay Scotches are each as distinct from each other as the regional Scotches are. Islay whisky tends to have a strong smoky, peaty flavor with a definite briny undertone. Some are less peaty, some less smoky, some sweeter, some more savory. Islay Scotches are in a class of their own. A little tip from experience: If you pick up a bottle of Islay Scotch that is too smoky for you, hold onto it for a few year (or try buying an older bottle). The smoky flavor is the first thing to mellow and it mellows significantly over time.