British Museum, London
The people of Pompeii cower in agony at the close of this extraordinary exhibition. In one chilling tableau an entire family – husband, wife and two children – lie together in positions of extreme pain and terror. The man and woman have their arms raised, fists clenched, as they brace against the extreme heat that hit this vainly sheltering little group when the volcano Vesuvius erupted in AD79. The children are even more pitiable. One is trying to get up out of the dying mother's lap. Another lies nearby, with a clearly preserved and mercifully tranquil-looking face.
The ash that buried Pompeii preserved its people. When the lost city started to be excavated in the 18th century, cavities were found to bear spooky imprints of faces, flesh, clothes. The 19th-century archaeologist Giuseppe Fiorelli discovered how to pour plaster of paris into the recesses to create the terrible, beautiful statues of suffering that leave you so haunted by what is undoubtedly one of the most momentous archaeological exhibitions ever staged.
I never witnessed the legendary Tutankhamun exhibition at the British Museum in 1972, but I have seen every exhibition there since Neil MacGregor became director in 2002 and this is the most moving by far. It is also the most timely. There have been too many news stories recently about ancient Roman buildings in Pompeii falling into ruin (after they were miraculously preserved). This majestic event will hopefully remind the world that Pompeii is not some tourist attraction to treat shabbily but the world's most revelatory survival of the human past.
It is not just about Pompeii but also Herculaneum. These were two flourishing cities in the wealthy region of Campania, a sun-kissed haunt of the rich, a Roman riviera where, the historians Tacitus and Suetonius tell us, the emperor Tiberius indulged in "disgusting vices" and where the owners of the so-called Villa of Papyri created a library of sceptical philosophy worthy of an ancient Richard Dawkins.
When the volcano destroyed and preserved these communities, the Roman empire was omnipotent. Legions marched on straight roads from Egypt to Britannia. Everywhere, they brought running water, heating, literacy. The first words ever written down in Britain were in Latin.
That might sound soft on a slave-owning imperial power. But you can't not love the Romans after seeing this exhibition. They are such an intimate mirror of ourselves. The reason Pompeii and Herculaneum fascinate is not just the preservation of an entire world in a moment of mass extinction, but the uncanny way that world reflects our own. Through a combination of slavery and hydraulic engineering, free Romans lived like modern people, surrounded by consumer goods and ingenious comforts.
This show is full of their stuff. The funny mosaic of a friendly-looking guard dog ("Cave canem" – beware of the dog); the amusing garden statue of the god Pan having sex with a goat; a mosaic of sea creatures that looks just like seafood stew you can eat today in nearby Naples. Wooden furniture, carbonised, survives in its crafted elegance. A joky picture of a skeleton with two wine jugs comments mordantly on the perils of booze. A life-sized bronze hare is a food mould, to make hare-shaped cakes or pâtés.
This exhibition is overflowing with beautiful art. And yet no one will leave it talking about art history. Art here is an accessory to life. The Romans were not the ancient Greeks, much as they tried to emulate them. Whereas classical Athens five centuries before the eruption of Vesuvius had created timeless classical monuments, the fascination of the art here is that it is so realistic and playful and so everyday.
It all comes together, so to speak, in the choice examples of Roman erotica. Pompeii's erotic paintings are amazingly frank. The Romans were practical people, and art does not get more practical than when it is pornographic. Pompeii may have had up to nine or maybe even 35 brothels, one of which is well-preserved. People had erotic paintings in their houses. In the exhibition's most unforgettable painting, a man and woman are trying out a new position while a slave waits in attendance, in case they need anything.
It is a glimpse of a world that is the same yet other. Roman life was fantastically civilised and truly barbaric. The lifestyle of the rich depended on using other human beings like we use machines. Only the industrial revolution would make it possible to reproduce such lifestyles without slaves. But when Vesuvius erupted, rich and poor, free man and slave died together.
A woman who fell as her villa was overwhelmed has been cast in epoxy resin: she was wearing simple, fine gold jewellery that mirrors the yellow translucent cast with its glimpses of bone beneath the flesh. The world that was lost when Vesuvius erupted is a world gained for curiosity and imagination. This historic and profound exhibition is an encounter with a flawed, fascinating and miraculous society, with sex and death, with the human epic that was Rome.