Pompeii was the largest of several towns buried by the paroxysmal eruption of Mt. Vesuvius that began at about noon on August 24 of 79 AD. The main phases of the eruption lasted into the next day, and there may have been smaller scale activity in following days -- no historical record survives of the immediate aftermath of the explosive first 24 hours. The pumice fall deposits at Pompeii, 8 kilometers south of Vesuvius, were 2.5 to 3 meters deep. Much thicker pyroclastic flow deposits (up to 20 meters deep) overwhelmed Herculanum and other towns on the eastern slope. Tephra (bits of lava and other materials blown out in pyroclastic flows) was found 74 miles away, and finer ash flew for hundred of miles before settling out. The pillar of smoke and ash was visible from Rome, and some people there claimed they had heard the volcano's rumbling.
The eruption was documented by contemporary historians and is universally accepted as having started on August 24th. However the archeological excavations of Pompeii suggest that it was buried 2 months later.
