In ancient times called Aìtnë, with its 135 km perimeter, Etna, the mythical Fùcina degli Dèi, is a very complex composite volcano, originated following the overlapping and juxtaposition of eruptive products emitted at different times through different magmatic ascent systems.
Developed, modified, destroyed and reconstructed through a multiplicity of geological events that have occurred over the course of many tens of thousands of years, this complex volcano represents a “response” to the complex process of lithospheric convergence between the South African plate and the Eurasian plate to the north as well as to the multiple geodynamic events that have characterized the Mediterranean basin. The thousands of lava flows, the immense quantities of slag, gravel, sand, ash and tuff emitted in the course of the incessant volcanic activity of this extraordinary natural thermodynamic machine, have destroyed and in some cases sealed or simply hidden by stratigraphic superimposition, the remains of various pre-existing eruptive centers.
The geological formation of Etna took place in four distinct phases:
THOLEIITI BASALI PHASES:
began about 500,000 years ago with submarine eruptions in the stretch of sea between Acitrezza and Acicastello, the remains of these eruptions are the Faraglioni of the Cyclops and the pillow lava that are found at the base of the Norman castle of Acicastello. These eruptions have contributed to fill the pre Etneo gulf.
Between 350,000 and 200,000 years ago, instead, very fluid fissure eruptions begin in the area between Paternò and Adrano.
TIMPE PHASE:
began about 220,000 years ago along the Ionian coast in a system of faults between Capomulini and Acireale called “Timpe” which led to the emission of porphyritic lavas originating from the first central eruptive eruptive centers (Calanna) and from fissural eruptions along the Timpa
PHASE OF THE ERUPTIVE CENTERS OF THE BOVE VALLEY:
Beginning around 110,000 years ago I see the displacement from the eruptive centers of the Val Calanna to the Valle del Bove and the passage from fissural to explosive and effusive eruptions. In this phase the eruptive centers of Trifoglietto, Giannicola, Salifizio, Cuvigghiuni and Tarderia are formed. in this phase it begins to form steep slopes typical of stratovolcanoes
STRATO-VULCANO PHASE:
This phase will lead to the formation of the largest eruptive center of Etna called the Elliptical volcano (about 3800mt) which is the main structure of Etna.
The collapse of this huge crater around 15,000 years ago led to the formation of the elliptical caldera, Pizzi Deneri to the NE and Punta Lucia to NO, representing the remains of the original edges of this volcanic depression. Only many hundreds of years after the end of the elliptic volcanism, in the southern part of the caldera, began to have a volcanic activity that would have led to the construction of the recent Mongibello or Etna. Around 9000 years ago a series of imposing landslides leads to the formation of the great depression called Valla del Bove. This imposing collapse brought to light the remains of the old eruptive centers of the Valle del Bove and  Ellittico that emerge along the valley walls.