A significant range of mountains in the Central Highlands, surrounded by the more extensive Grampian Mountains, the Cairngorms (Gael: Am Monadh Ruadh - the Red Mountains) form a high-plateau around their sixth highest peak Cairn Gorm (1245m / 4085 feet). This plateau is the highest and coldest in Britain. The other significant peaks, which include most of the highest in Scotland, are Ben Macdhui (1309m / 4295 feet), Braeriach (1296m / 4252 feet), Cairn Toul (1293m / 4242 feet), Carn na Criche (1265m / 4150 feet) and Sgor an Lochain Uaine (1258m / 4127 feet). The range crosses between Aberdeenshire, Highland and Moray council areas.
Geologically distinct, the mountains are formed of pink granite and were once the root of an ancient volcano which erupted above the subducting plate forced under Northern Scotland as the ancient Iapetus Ocean closed around 450 million years ago. The landscape today is carved by glaciation, although the ice sheet covering the high-plateau is thought to have remained stable for millennia, frozen to the ground and stationary. The surrounding valleys are littered with deposits representing the retreat of glaciers. Granite tors are common, formed by weathering, together with a range of periglacial features.
The climate here is unique in Britain, receiving the greatest amount of snow in the country, with 76.2 days of snow or sleet falling in an average year. While lacking glaciers, there are snow patches that persist from year to year. The weather is unpredictable and strong winds are common on the plateau. Avalanches are not uncommon in winter and flash floods occur in the spring and early summer. The summers on the plateau remain cool, with temperatures rarely exceeding 15°C.
The area is also of ecological interest, comprising a sub-Arctic environment, with tundra-like characteristics, limited soil and vegetation. Much of the ground and rocks are covered by lichen and mosses. Plants include the Mat Grass and Carnation Sedge with flowers such as Alpine Lady's Mantle (Alchemilla alpina), Alpine Milk-vetch (Astragalus alpinus), Alpine Sow Thistle (Cicerbita alpina), Dwarf Cornel (Cornus suecica), Starry Saxifrage (Saxifraga stellaris) and Trailing Azalea (Loiseleuria procumbens), that burst into life each spring after the snow melts. The plateau is home to bird species such as ptarmigan, dotterel, snow bunting, curlew and red grouse, as well as mammals such as mountain hare. The mountains also support Britain's only herd of free-ranging reindeer, which were re-introduced in 1952, with the Cairngorm Reindeer Centre in Glen More open to the public.
The mountains give their name to the Cairngorms National Park, the largest park in the UK, which extends well beyond the Cairngorms into the surrounding Grampian Mountains.
Although the mountains are popular for hill-walking, ski touring and climbing, they are relatively inaccessible except for a road which leads to the ski centre at Cairngorm Mountain, on the northern side of the range, and from there the relatively short Cairngorm Mountain Railway which reaches the summit of Cairn Gorm itself.
