Geological history of Etna.
Over the centuries the appearance of Mount Etna has altered.
In 1865 the summit was at 3,313 m (10,867 ft);
in 1932 it was at 3,263 m (10,703 ft) high.
Eruptions in the central crater are rare,
but they are frequent in the side vents,
and here they create smaller secondary cones.
On the eastern slope of Mount Etna is a huge chasm known as the Valle del Bove,
the result of a immense explosion.
Mount Etna is a protected area of 143.000 acres in size,
and offers many opportunities for excursions,
attracting thousands of visitors every year.
A popular excursion is from Zafferana Etnea to the Valle del Bove,
the spectacular hollow whose shape was changed by the 1992 eruptions.
The hike up to the large craters at the summit is not to be missed.
Start off at the Rifugio Sapienza and Rifugio Citelli hostels and Piano Provenzana
(after suffering eruption damage,
these hiker centers are now being rebuilt).
A trip around the Mountain is also thrilling:
from the Sapienza to Monte Scavo camp.
There are also several lava grottoes.
Nature on Mount Etna.
Despite the many eruptions and the bitter cold that freezes the terrain in winter,
many species of plants have succeeded in colonizing the lava soil.
At high altitudes you can see small lichens,
camomile and soapwort on the slopes.
Poplars thrive in the more umid areas.
Further down are woods of beech,
birch, larch and corsican pine.
Centuries of hunting have reduced the animal population,
though there are still rabbits,
weasels, wildcats and foxes,
while the main bird species are the Sicilian partridge.
Skiing on Etna.
Although there are few chair lifts,
skiing on Mount Etna is a unique experience.
Besides the regular ski runs you can also do cross-country skiing or mountain climbing in the snow.
Rifugio Sapienza.
At over 1,800 m (5,904 feet),
the Sapienza hostel is a base for hikers in the summer and for skiers in winter.