Speyside is located in Highland, East of Inverness.
The Speyside single malts are noted in general for their elegance and complexity, and often a refined smokiness. Beyond that, they have two extremes: the big, sherryish type, as typified by The Macallan, Glenfarclas and Aberlour; and the lighter, more subtle style. Within Speyside, the River Livet is so famous that its name is borrowed by some whiskies from far beyond its glen. Only one may call itself The Glenlivet, only Braes of Glenlivet and Tamnavulin are produced in the valley, and only Tomintoul in the parish. These are all delicate malts, and it could be more tentatively argued that other valleys have malts that share certain characteristics. The Highland region includes a good few coastal and island malts, but one peninsula and just one island have been of such historical importance in the industry that they are each regarded as being regions in their own right. Extracted from Michael Jackson's Malt Whisky Companion
Source www.bbr.com :
To some Speyside represents the jewel in whisky’s crown. Speyside is the home of legal whisky production and it’s best known examples. Around the world Glenlivet, Macallan, Glenfiddich, Glenrothes and Glenfarclas typify all that whisky, at it’s best has to offer. At it’s heart running from the Monadhliath mountains north to the sea, is the River Spey. It is the fastest flowing river in Britain, and also well known for its salmon fishing.
Speyside is the principal whisky-producing region: Speyside has within it some forty-six operating distilleries - over half the total number in the entire Scotland.
Speysides are essentially sweet whiskies. They have little peaty character They are typically highly perfumed, feminine and elegant.
The classical nature of Speyside’s malts means that a number of the finest malts are used almost exclusively for blending. It is the top Speysider’s that give good blends their ‘Top Dressing’.
Malts such as Mortlach, Glen Elgin, Strathmill and Benrinnes are rarely found as distillery bottlings, however when individual casks are tracked down by independent bottlers such as Berrys’ Own Selection Single Malt Whiskies the resultant whisky can be quite wonderful.