Campanian Ignimbrite eruption
40000 BCE.
Shown on the map at 40.827°, 14.139°.
The Campanian Ignimbrite eruption (CI, also CI eruption) was a major volcanic eruption in the Mediterranean during the late Quaternary, classified 7 on the Volcanic Explosivity Index (VEI). The event has been attributed to the Archiflegreo volcano, the 12-by-15-kilometre-wide (7.5 mi × 9.3 mi) caldera of the Phlegraean Fields, located 20 km (12 mi) west of Mount Vesuvius under the western outskirts of the city of Naples and the Gulf of Pozzuoli, Italy. It was the largest explosive volcanic event in Europe in the past 200,000 years, and the largest eruption of Campi Fleigrei caldera. Estimates of the date and magnitude of the eruption(s), and the amount of ejected material have varied considerably during several centuries the site has been studied. This applies to most significant volcanic events that originated in the Campanian Plain, as it is one of the most complex volcanic structures in the world.
Text from the Wikipedia article Campanian Ignimbrite eruption, licensed CC BY-SA 4.0.