Etna’s explosions are mainly effusive. Its explosive acitivity is limited to vulcanian phases, ultra vulcanian, strombolian and more rarely; Hawaiian type lava fountains. Only a few non recent deposits have been formed by pyroclastic products deriving from real explosive activity. this is why Etna isn’t considered as very dangerous. Listed below are some of the most important eruptions: 693 – Destroyed ancient Katane, partially covered Armenano and led to the creation of Lake Nicito.
1329 – Three lava flows : one covered Mascali, another reached the sea north of Acireale and a third got threateningly close to Catania.
1381 – The eruption reached the sea and covered the port Ulysses in the Ognina area of Catania.

1669 – The eruption which was preceded by a series of earthquakes, generating an 18km long fissure (from Nicolosi until near the main crater).
The lava swept over several towns including Nicolosi, Belpasso, Mompilieri, Mascalucia, Camporotondo, S.Giovanni Galermo, S. Pietro Clarenza and Misterbianco.  It managed to reach Catania, pouring into Ursino Castle’s moat, covering Amenano and Lake Nicito.
1865 – Monti Sartorius were formed.
1892 – Monti Silvestri were formed.
1911 – Impresive explosive/effusive activity led to the creation of the North East crater.
1928 – Mascali was destroyed.
1950/51 – A long effusive eruption threatened Milo, Fornazzo and Zafferana.
1971 – The Gememellaro Volcanology observatory and part of the cable car were buried by lava.
1981- The lava reached the Alcantara river and got close to the town of Randazzo.
1983 – First attempts to deviate the lava flow with explosives.
1991/1993 – Lava invaded the Val Calanna and threatened Zafferana.
2001 – The eruption caused much disruption due to falling volcanic ash, the upper part of the ski station was destroyed as were the cable car pylons, lava bombs of noteworthy dimensions were produced during the eruption.
2002/3 – The lava reached the piazzale of Piano Provenzana destroying ski facilities and blocking the Linguaglossa provincial road to Piano Provenzana due to cracks which had formed in the road surface.
There were serious disruptions to Catania due to the ash which even got to Messina.
The eruption was accompanied by a series of earthquakes whose most violent tremors damaged the town of Santa Venerina.