Etna history has been characterized by the construction of numerous volcanic edifices and  catastrophic collapse of these structures that caused the formation of Valle del Bove, crater and cones.

Etna's eastern flank suffered a catastrophic collapse. A huge depression was thus formed in the side of the volcano, now known as Valle del Bove (Valley of the oxen). Its north-south width is 5.5 km while its extension from west to east is 7 km. it is roughly horse-shoe shaped.
 
The origin of the name "Valle del Bove" is mysterious. Actually the name might suggest that it was once possible to use parts of it as pasture ground for cattle. Presently a large part of the floor of the Valle del Bove is covered by lavas erupted during the 20th century, making it one of the most hostile and least accessible areas of the volcano in sicily.

The circumstances, the age and mt etna info of the collapse that created the Valle del Bove have remained mysterious for a long time. Before the collapse, there were probably ice and snow fields in the summit area of the volcano, which fed a number of rivers .

The Valle del Bove is a very important area for studies of the geological evolution of Etna and for finding mount etna information, for in its walls the traces of numerous older edifices pre-dating the presently active volcano are exposed. Here the first evidence for the eventful history of the volcano has been found.

Summit activity occurs at four craters: the Voragine and the Bocca Nuova, which lie in the area of the former Central Crater, and the Northeast (NE) and Southeast (SE) Craters. The latter have built sizeable cones  referred to as the Northeast and Southeast Crater cones.

 

In October 1945, a small collapse pit formed in the northeastern part of the Central Crater.  This depression, the site of frequent activity, gradually spread by collapse and explosive eruptions. It is now known as the "Voragine" or , but local people call it "Centrale".

In 1968, a small pit , the Bocca Nuova, the "new mouth" , opened on the West flank of the large cone formed in 1964 around the Voragine.
Both the NE and the SE Craters started in a very similar manner as collapse pits on the flanks of the main summit cone.

The Southeast Crater life began during the 1971 eruption. Eruptive fractures opened pouring lava flows that caused serious damage to forests,  gardens, and  buildings.
 
Northeast Craters birth occurred in a period characterized by Strombolian bursts and slow lava effusion. The largest of these formed in 1970 and was nicknamed "Nordestino" (little Northeast) by the local mountain guides

Many of Etna's flank cones have horseshoe-shaped craters and owe their morphology to the outflow of lava from their vents on the downslope side. The size of the flank cones varies significantly depending on the explosivity and duration of an eruption. One of the most impressive chains of eruptive cones is Monti Silvestri near Rifugio Sapienza - Nicolosi, on the southern flank of Etna.

 

Some of etna cones are:

• Monte Moio is composed of at least two overlapping cones with three craters. Although its age is not known precisely, the youthful shape of the cone indicates that it formed during the last few thousand years.

• Monti Rossi, the cone of the 1669 eruption  formed at eruptive vent of the 1669 eruption on Etna's south flank. The cone is now a public park.

• Montagnola  is a large pyroclastic cone formed in the 1763 eruption; its lava flows formed a particular ridge.

• Monti Calcarazzi were built by another eruption three years later. In 1892, an eruption led to the formation of yet another crater row, the Monti Silvestri.

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