An earthquake caused great damage to the Roman city nearly two decades earlier, but on Aug. 24, AD 79, few in Pompeii could imagine that it heralded the total destruction that was to come.
In the early hours of the afternoon, there was a frightening roar as Mount Vesuvius unexpectedly blew its top, spreading burning rock, flaming cinders, fragments of lava, pumice, and deadly fumes over the prosperous city. A rain of ashes followed.
"What is most striking today is how clearly one can see that daily life was suddenly interrupted," says archaeologist Irene Bragantini.
As they fled in confusion, Pompeians dropped what they were carrying, left house keys and change in the taverns, left their dogs tied up. About 2,000 of the city's estimated 15,000 inhabitants perished under the hot ash. A vivid eyewitness report of the tragedy is preserved in two letters by Roman writer Pliny the Younger.
For the next 17 centuries, Pompeii, the town of Herculaneum, and several nearby villas disappeared, protected beneath a layer of pumice-stone and ash 19 to 23 feet deep. The ruins of ancient Pompeii were first uncovered in the 16th century, but it wasn't until 1748 that excavations began, slowly revealing a city frozen in time.
"At the start, excavators were curious about the way people lived in Pompeii ... how they kept warm and how they washed, basically, the mechanisms of daily life," says Ms. Bragantini. "This century, studies have concentrated on what happened after the earthquake, on the city's political situation at the time of the disaster, and on why no one returned to Pompeii after the the volcano's eruption.
"One of the theories is that people at the time were very superstitious. Although the region where Pompeii stands was a very fertile one for agriculture, no one wanted to go back to a city where thousands had been killed," she says.
Two-thirds of Pompeii have been uncovered, giving a clear picture of how it was built and organized. The Forum, around which most public buildings were built, stands to the west, and the amphitheater to the east.
"There is even a large quantity of ancient graffiti on the walls. The most common inscriptions refer to electoral campaigns or advertisements for public games," says the archaeologist.
Hundreds of private homes have provided a unique source of information. The objects found reveal the lifestyles of the sculptor, the toolmaker, and the gem-cutter. A collection of surgical instruments found in one house constitute some of the most important evidence on ancient medical practice.