Eruption of Mount Vesuvius

Mount Vesuvius, located near Herculaneum and Stabiae, erupted many times, but very notably in the year 79, on August 24. Pompeii, the closest town, was buried under ten feet of volcanic ash and is visited for the preserved plaster casts of the city that was buried so quickly. Pliny the Younger was stationed relatively closely, and watched the eruption occur, but his uncle, Pliny the Elder was there, and died a hero as he attempted to evacuate the area.

http://ancienthistory.about.com/od/pompeii/p/MtVesuvius.htm