What happened
In AD 79 Mount Vesuvius erupted catastrophically, burying the Roman towns of Pompeii and Herculaneum under volcanic ash and pyroclastic flows.
Background
The Bay of Naples was prosperous and densely settled. Pliny the Younger described the eruption and the death of his uncle Pliny the Elder in letters, so such eruptions are now called Plinian. The year AD 79 is firm, but the traditional day of 24 August is debated, with some evidence pointing to autumn, so the day is uncertain.
Consequences
Thousands died, but the ash preserved the towns in extraordinary detail. Their excavation from the 18th century opened an unmatched window into Roman daily life, and Pompeii is a major archaeological site today.