Etna is the highest active volcano in Europe, is located in northeastern Sicily and is the result of a variety of geological events that have taken place over many tens of thousands of years. With its huge bulk, overlooking the Ionian Sea to the east, north is bounded by the river Alcantara, who dug his bed of lava soil gave rise to wonderful narrow gorges, which are now part of the Gorges of the Alcantara River Park . To the west and southwest Etna is instead bounded by the river Simeto.Etna is currently about 3330 meters high, extending over a perimeter of about 210 km and an area of 1600 square kilometers. During periods of intense volcanic activity, lava may flow out from hundreds of craters found on the flanks of the volcano, these craters are collected in over 260 eruptive systems. The current shape of the volcano, the height of which undergoes constant change due to the accumulation of materials or collapse of the walls, was built on the old volcanoes Trifoglietto, whose collapse has generated the pit crater of the Valle del Bove, Mount Etna and, gebel from Arabic to describe the "mountain of mountains", which is still in business. The top part of the volcano is formed from the central crater, Voragine and Bocca Nuova crater at an altitude of 1911 North-East and South-East crater at an altitude of 1971 meters above sea level. In addition to the craters are of particular interest in the Hillock and Monti Silvestri. The Hillock is one of the most impressive adventive cones Etna rises south of the Central Crater, high on the southern side where it is implanted at an altitude of 2,500 meters following the eruption of 1763. The Monti Silvestri were formed after the eruption of 1892, and between the Upper and Lower Mount Silvestri is a road that Zafferana and Nicolosi to Rifugio Sapienza and the square of the cable car, half of all visitors who are about to begin climbing the volcano. At 2900 meters altitude is the famous Tower of the Philosopher, a building named in memory of Empedocles, the philosopher from Agrigento who climbed the volcano to study the phenomena and put its house. Legend has it that the philosopher died, plunging into the mouth of the volcano, but it is not clear if this was done accidentally or on purpose.
The excursions to the Etna summit craters can be made with qualified local guides, bus and 4x4 off-road, the company that runs the cable car is able to provide these services regularly authorized, but there are many parallel organizations that perform the same type service.