Other volcanoes of great importance are Hekla and Katla, which have erupted many times in the past and are always under observation by the Icelandic civil protection. There are four historical eruptions that are particularly worth mentioning, however: the first, in 1783, was that of Laki, in southern Iceland, when 14 cubic kilometers of lava were emitted from the eruptive fissure called Lakagìgar, 25 km long. It was the largest lava flow in history, a record that has not yet been broken anywhere on the planet. Unfortunately, together with the lava, huge clouds of sulfur dioxide and fluorine came out from the eruptive fissure of Lakagìgar; the gases, once deposited on the island's land, contaminated the vegetation leading to the death of 50% of the livestock and the devastating famine that consequently followed. More recently, in the 20th century, a sub-glacial eruption below the great Vatnajökull glacier has alarmed the Icelandic population.
From September 30th to October 13, 1996, a long eruptive fissure was activated, which managed to melt about 3 cubic kilometers of water that nonetheless remained confined within the glacier. Icelandic geologists were expecting that at many moment the enormous pressure of melt water could shatter the side of the glacier and escape outside. All of this happened right on time, between November 4 and 7th, 1996. It was a real Jökulhlaup (a term that can be translated as "flood") of biblical dimensions, a real tsunami of glacial meltwater that completely devastated the region south of the glacier, and whose signs can be seen still today with great clarity. Another eruption that we all remember is that of Eyjafjallajökull, a volcano with an unpronounceable name which, between March and April 2010, caused an uproar in aviation around the world.
It all started with a purely "effusive" eruption, which is limited to the emission of spectacular lava fountains. Subsequently, however, the magma rising from the conduit came into contact with the summit glacier of the volcano. The explosive combination of magma and glacial melt water triggered a large explosive eruption of the phreatic-magmatic type which consequently emitted an eruptive column of ashes that was directed, carried by the winds, towards the South-South-West, invading the Scandinavian countries and Great Britain. On April 15, 2010, the closure of the airspaces and airports in numerous countries in central and northern Europe was decreed, causing several hundred million euro in damage. The current eruption taking place in the southwest of Iceland, contrary to those already described, is a real boon for tourists. On the Reykjanes peninsula, the eruption of the Fagradalsfjall volcano began on March 19, 2021, with spectacular lava fountains visible from the capital. Tens of thousands of visitors have already flocked to admire this miracle of nature, which represents for Iceland only a tiny piece of the fascinating volcanic history of this unique island in the world.