Pompeii buried by Vesuvius

The story

An ordinary town on an ordinary day

In AD 79 Pompeii was a Roman town in Campania, near the mouth of the river Sarno and a few kilometres from the sea. Perhaps 10,000 to 12,000 people lived there: shopkeepers, craftsmen, slaves, freedmen, a few rich families with large decorated villas. There was the forum with its temples, two theatres, the baths, a stone amphitheatre (the oldest one to survive), dozens of shops where people ate at the counter, bakeries, laundries and taverns. On the walls people wrote everything: election notices, prices, greetings, jokes, insults.

Above the town stood Vesuvius. For the Romans it was a green mountain, covered with vineyards: nobody knew it was a sleeping volcano. Seventeen years earlier, in AD 62 (or 63), a strong earthquake had damaged Pompeii, and in many houses workmen were still repairing walls and frescoes. Nobody connected that shock with the mountain.

The eruption: two terrible days

On the day of the eruption, at about one in the afternoon, an enormous cloud rose from Vesuvius. Pliny the Younger, who was at Misenum, on the other side of the Bay of Naples, compared it to a pine tree: a very tall trunk that spread out into branches at the top. Today we know it was a column of gas, ash and stones rising for tens of kilometres.

The wind pushed the cloud towards the south-east, right over Pompeii. For many hours a thick rain of pumice and lapilli, small light stones full of holes, fell on the town. The sky became as dark as night. Roofs collapsed under the weight, which grew from hour to hour. Many inhabitants fled at once, taking with them what they could: coins, jewellery, lamps. Others stayed, shut in their homes, waiting for it to end.

The next morning the deadliest phase arrived. The column of ash collapsed and pyroclastic currents rushed down from the volcano: avalanches of boiling gas, ash and rock fragments, racing at great speed down the sides of the mountain. Herculaneum, closer to Vesuvius, was hit first and buried under a blanket of material in places more than 20 metres deep. Then the currents reached Pompeii: those who had stayed died within moments from the heat and the gases. Stabiae, Oplontis and many country villas were buried too.

The witness: Pliny the Younger

We know so much about the eruption thanks to a boy of 17. Pliny the Younger was living at Misenum with his uncle, Pliny the Elder, a scientist and commander of the Roman fleet. When he saw the cloud, his uncle set out with the ships to get closer and bring help to the people of the coast. Arriving at Stabiae, at the house of a friend, he spent the night there; the next morning, on the beach, he died, perhaps suffocated by the gases or struck down by a sudden illness.

About twenty-five years later the historian Tacitus asked Pliny the Younger to tell him how his uncle had died. Pliny replied with two letters, which have survived: in the first he describes his uncle's voyage, in the second his own escape from Misenum with his mother, amid earthquake shocks, ash falling like snow and terrified people crying out in the dark. It is the first precise description of a volcanic eruption: this is why volcanologists still call eruptions of this kind “Plinian eruptions”.

On what day did it happen?

For centuries it was said that the eruption began on 24 August 79, because this date is read in many medieval copies of Pliny's letters, although not all agree. But archaeologists had doubts: at Pompeii they find autumn fruits such as pomegranates, braziers lit in the houses and wine already put to ferment in the big jars. In 2018, in a house that had just been excavated, an inscription in charcoal appeared with the date of 17 October: since charcoal rubs off quickly, it must have been written recently. For this reason some scholars think it probable that the eruption took place on 24 October 79. The year is certain; the day remains debated.

The rediscovered city

After the eruption the coast was unrecognisable and Pompeii vanished under 4 to 6 metres of volcanic material. The emperor Titus sent officials to help the survivors, but the city was never rebuilt and in time even the memory of it was lost. Real excavations began only in the 18th century, under King Charles of Bourbon: first at Herculaneum (1738) and then at Pompeii (1748). In 1763 an inscription confirmed that this was indeed Pompeii.

In the 19th century the archaeologist Giuseppe Fiorelli had a brilliant idea. The bodies of the victims, wrapped in ash, had decayed, leaving hollows, like moulds. Fiorelli filled them with liquid plaster: when the plaster hardened and the ash around it was removed, the shapes of the people appeared in the last moment of their lives. These casts are among the most moving images in archaeology.

Today at Pompeii you walk on streets with the ruts left by carts, you enter houses, you read the writing on the walls. Part of the city has still not been excavated, and every year archaeologists find something new: frescoes, objects, whole rooms.