Eruption of Mount Vesuvius

Have you ever wondered what it'll be like to watch a volcano erupt in real life? To watch it up close and not through a television screen, through the internet or in pictures posted in the papers. To watch in awe as one of nature's most spectacular yet deadly occurrences takes place before your eyes.

Regarded as one of the most dangerous volcanoes in the world today, Mount Vesuvius is most 'renowned' for its catastrophic eruption in the year of 79 AD with the exact date and time unclear but believing to have lasted for about two days. The eruption obliterated the two Roman cities of Herculaneum and Pompeii which were located to the West and Southeast of Vesuvius respectively. The estimated death toll was put around 16,000 lives with ash and dust clouds covering most of its southern regions. Almost everyone in Pompeii and Herculaneum was unable to flee for their lives and were killed.

Artist impression of the eruption of Mount Vesuvius from Pompeii.

Preceding to the great eruption of 79 AD, a major earthquake struck the Bay of Naples adjacent to Pompeii 17 years beforehand. It is common knowledge that seismic activity within the vicinity of volcanoes are usually either directly or indirectly related to volcanic activity. The movement of deep underground seismic plates located many kilometers beneath the surface coupled with magma flow causes tremors that reverberate in all directions. On the surface, major tremors shake the very earth thus disturbing the volcano and causing an immense release of pressure from volcanoes. In the case of Vesuvius, the pressure build up was due to ground water seeping from the surrounding into faults within the volcano. The water heated up and formed pockets of extremely hot gas with lots of energy just waiting to be released into the open. Needless to say when the chance for the volcano to 'let loose some steam' came, it did not hold back.

A majority of the lives lost and damage done are actually not due to the eruption itself or lava. An occurrence known as pyroclastic flow which succeeds the volcano eruptions cause the largest percentage of human casualties in any volcanic eruption. Pyroclastic flow is a current of superheated gas and rocks that is thrown out by the volcano when it erupts. The currents can reach speeds of up to 700 km/h and temperatures of up to 1000°C. These devastating currents stay close to the ground and spread outwards from the mouth of the volcano.

Within one day after the eruption, pyroclastic flow from Vesuvius began engulfing the city of Herculaneum. Although the temperature of the currents from Vesuvius was relatively low, about 300°C, the density of the clouds were thick enough to knock down entire buildings. The next three surges reached the city of Pompeii and destroyed it. Those unlucky enough to be caught in the streets when the currents hit were instantly burried under rocks or suffocated to death due to ash inhalation. Anybody hiding in buildings or structures could not have escaped as the city was surrounded by gases of incinerating temperatures, meaning that they were either killed when the buildings collapsed on them or were 'cooked' to death.

The great eruption of 79 AD had rather permanent effects on the geography of the mountain and its immediate vicinity. After that eruption, the summit of mount Vesuvius had been changed considerably and was more deformed with a larger crater. The Sarno River nearby the volcano had also been affected with its river being redirected in a slightly different direction and most of its river basin being burried during that period. The city of Pompeii was very well preserved underneath the pumice, ash and layers of earth that covered it in the many years after that until its accidental discovery in the 18th century.

Due to its past history, the Italian government has put in place an emergency evacuation plan should an eruption occur. The plan is tailored for an eruption of the worst kind similar in scale to that of the 79 AD eruption with 14-20 days notice prior to an eruption. The plan comprises of the emergency evacuation of 600,000 people in the immediate danger zone in the event of an eruption by means of ferries, trains, cars and buses. The government has also put in place ongoing policies in order to reduce the population of people around the presently inactive volcano. Among these are the establishing of a national park reserve around the volcano to prevent further development closer to it and to provide financial assistance for those who wish to move away from the region. The purpose of these policies are to reduce the number of people needed to be evacuated and the time required to evacuate the overall population. After all, better safe than sorry.


Today the region around Mount Vesuvius is home to around 3 million people and is one of the most densely populated volcanic regions in the world. The most recent eruption of Mount Vesuvius took place in the spring of 1944 during World War 2 where the fallout from the dust and debris damaged a USAAF airfield in Italy. With a period of roughly 7 decades since the last eruption, it has been the longest period of inactivity from Vesuvius in over 400 years.