Three-thousander

Three-thousanders are mountains with a height of between 3,000, but less than 4,000 metres above sea level. Similar terms are commonly used for mountains of other height brackets e. g. four-thousanders or eight-thousanders. In Britain, the term may refer to mountains above 3,000 feet.

In temperate latitudes three-thousanders play an important role, because even in summer they lie below the zero degree line for weeks. Thus the chains of three-thousanders always form important climatic divides and support glaciation - in the Alps the 3,000-metre contour is roughly the general limit of the "nival step"; only a few glaciated mountains are under 3,000 metres (the Dachstein, the easternmost glaciated mountain in the Alps, is, at 2,995 m, not a three-thousander). In the Mediterranean, however, the three-thousanders remain free of ice and, in the tropics, they are almost insignificant from a climatic perspective; here the snow line lies at around 4,500 to 5,000 metres, and in the dry continental areas (Trans-Himalayas, Andes) it may be up to 6,500 metres high.

The designation "three-thousander" is often used for touristic reasons where only a few individual summits exceed this height – e. g. in the Southern Alps, in the eastern part of Austria, in the Limestone Alps, in the Pyrenees or the rest of Europe. For example, the Parseierspitze in the Lechtal Alps at 3,036 m is the only three-thousander in the Northern Limestone Alps.

In the Alps or Pyrenees, expeditions to areas of over 3,000 metres, with their often steep mountainsides and sudden changes in weather conditions, require mountaineers to have considerable experience and weatherproof equipment, which distinguishes them from ascents of many two-thousanders.

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Wikipedia