On August 24 in A.D. 79, just short of two millennia ago, Mt. Vesuvius, an active volcano in southern Italy, destroyed the cities of Pompeii, Herculaneum and other nearby towns. Based on accounts by Pliny the Younger to the Roman historian Tacitus, the eruption supposedly began around noon. The volcano began showering Pompeii with lapilli, small pieces of solidified lava. By the following morning, ash had buried Herculaneum, Oplontis and finally Pompeii.
Vesuvius is considered a stratovolcano with steep sides formed by repeated flows of various volcanic material. The eruption in A.D. 79 is now referred to as a Plinian eruption, because of Pliny’s detailed description of its nature. A Plinian eruption is characterized by pine-shaped clouds that form above the volcano’s crater and the variety of hazardous materials the volcano releases. In Herculaneum, four surges from the volcano covered the town with 75 feet of ash and volcanic material.
Excavation of Pompeii began in the mid-18th century, primarily to recover art objects for the private collection of Charles III. As the area changed hands between France and Italy, the excavations continued into the 21st century with a number of different archeologists. Today, 44 hectares (1 hectare equals 2.7 acres) of the 66 hectares of the urban area are uncovered; the other 22 hectares will remain buried to preserve their artifacts. (Pompeii: Its Discovery and Excavation)
For more on the A.D. 79 eruption of Mt. Vesuvius, see:
Ghosts of Vesuvius by Charles Pellegrino
Pompeii: A City Rediscovered (video)
The Lost World of Pompeii by Colin Amery
Pompeii: The Day a City Died by Robert Etienne
The Last Days of Pompeii by Edward Bulwer Lytton (fiction)