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Etna or Aetna (both: ĕtˈnə), volcano, 10,958 ft (3,340 m) high, on the east coast of Sicily, S Italy. One of the most active volcanoes in the world, it also is the highest active volcano in Europe. The shape and height of its central cone have often been changed by eruptions. There are more than 260 lesser craters on the slopes, formed by lateral eruptions. The southeastern slope is cut by a deep (2,000–4,000-ft/610–1219-m), precipitous cleft, the Valle del Bove. The first known eruption occurred in 475 B.C. and was described by Pindar and Aeschylus. Of the numerous later eruptions, often accompanied by earthquakes, those of 1169 and 1669 were the most destructive; the most recent major eruption occurred in 1992.
The wide base of Mt. Etna, c.93 mi (150 km) in circumference, is encircled by a railroad. The fertile lower slopes are densely populated agricultural areas. Up to 1,600 ft (488 m) the vegetation is subtropical, yielding citrus fruit, bananas, and figs; between 1,600 and 4,300 ft (488–1,311 m) is a temperate zone, with vineyards and various fruit trees; from there to c.7,000 ft (2,130 m) are chestnut, birch, and pine woods; above, there is a desolate waste of lava and ashes. Near the top there is snow most of the year. There is an observatory at 9,650 ft (2,941 m). A motor road from Nicolosi, NW of Catania, to the 6,170-ft (1,881-m) level was completed in 1935.
(also Aetna), the highest active volcano in Europe. Etna is located in Italy, in the eastern part of the island of Sicily, and has an elevation of 3,340 m (according to some Italian sources, 3,263 m).
Etna is cone shaped, with gently inclined lower slopes and steeper upper slopes. Its base is 40–60 km in diameter, and the crater at its summit is about 400 m in diameter. There are about 900 parasitic cones on its slopes, with heights ranging from a few meters to 200–300 m.
Formed during the Anthropogenic (Quaternary), Etna is highly active, with more than 125 cycles of eruptions recorded in history. The disastrous eruption of 1669, in which about 100,000 people are believed to have perished, partially destroyed the city of Catania. The most recent eruption was in 1981.
Most eruptions are through the lateral cones; the lavas emitted are composed of trachytes, dolerites, and basalts. In the intervals between eruptions, gases and water vapor are released. Earth quakes occur frequently. Fields, orchards, and vineyards are found on the fertile volcanic soils up to elevations of 800–900 m; Mediterranean shrubs and forested sections with oak, beech, hornbeam, maple, and Corsican pine are encountered at higher elevations. Barberry and Astragalus thickets also grow in this area. During several months of the year, a snow cover is found at elevations above 1,500 m.
V. I. VLODAVETS