Hannibal's crossing of the Alps is a fact that has been handed down for millennia and one of the school memories that best withstands the passage of time. Barcide set off in 218 BC from Nova Carthago (Cartagena), crossed the eastern Pyrenees at the Col de la Perche and reached the Alps via an Alpine pass in Italy. Which 'gateway' the leader used to enter Italy remains a matter of debate, although studies tend to favour the Moncenisio. The two ancient sources (Polybius and Livy) are particularly rich in detail when describing the crossing, but the lack of precise topographical references has led to subsequent uncertainty and, therefore, to many studies: since ancient times, this feat has attracted considerable interest. Hannibal set off at the end of May and reached the top of the pass 'at the moment when the Pleiades constellation sets', i.e. in the last ten days of October. The march across the Alps must undoubtedly have been exhausting beyond words: the soldiers and animals were already worn out from travelling more than 1,500 kilometres, and the Alps were already covered in the first snow of September. The army was never seriously attacked by the local populations, but they did engage in guerrilla warfare, as the gorges and hills were perfect places to ambush a column that stretched for kilometres, from the elephants at the front to the horses at the rear. It is worth mentioning a stratagem that Hannibal used to escape this pressing enemy: at nightfall, he had the camp fires lit, but did not stop the march, thus deceiving the natives and allowing the army to move away undisturbed from the ambush sites. The last stretch of the march was characterised by storms, snow and bad weather, and the long procession arrived at the pass almost at the end of its strength. Only the sight of the sunset over the Italian valleys below gave them the strength to continue. Africa thus entered Europe, but at a very high cost: sources say that the Carthaginians numbered more than 100,000 at the start and that 20,000 infantrymen and 6,000 horses arrived in Italy. The estimate of the number of soldiers at the start is undoubtedly too high, but these figures reveal the difficulty and magnitude of the undertaking. Let us not forget, however, that, to quote Gianni Granzotto's book 'Hannibal', 'Hannibal is not important in history for having crossed the Alps, but for what he did after he crossed them, during the fifteen years that followed'.