The Rhone rises north-west of the head of the Adriatic on the northern slope of the Alps, and running in a south-westerly direction, falls into the Sardinian Sea. A great part of its course is through a deep valley, to the north of which lives the Celtic tribe of the Ardyes, while on the south it is bounded for its whole extent by the northern spurs of the Alps. The plain of the Po which I described above at length is separated from the Rhone valley by the lofty main chain of these mountains, which starting from Marseilles extends to the head of the Adriatic. It is this chain which Hannibal now crossed to enter Italy from the Rhone valley.
Some of the writers who have described this passage of the Alps, from the wish to impress their readers by the marvels they recount of these mountains, are betrayed into two vices ever most alien to true history; for they are compelled to make both false statements and statements which contradict each other. While on the one hand introducing Hannibal as a commander of unequalled courage and foresight, they incontestably represent him to us as entirely wanting in prudence, and again, being unable to bring their series of falsehoods to any close or issue they introduce gods and the sons of gods into the sober history of facts. By representing the Alps as being so steep and rugged that not only horses and troops accompanied by elephants, but even active men on foot would have difficulty in passing, and at the same time picturing to us the desolation of the country as being such, that unless some god or hero had met Hannibal and showed him the way, his whole army would have gone astray and perished utterly, they unquestionably fall into both the above vices.
For in the first place can we imagine a more imprudent general or a more incompetent leader than Hannibal would have been, if with so large an army under his command and all his hopes of ultimate success resting on it, he did not know the roads and the country, as these writers say, and had absolutely no idea where he was marching or against whom, or in fact if his enterprise were feasible or not? What they would have us believe is that Hannibal, who had met with no check to diminish his high hopes of success, ventured on a course that no general, even after a crushing defeat and utterly at his wits’ end, would take, to march, that is, into a country as to which he had no information.
Similarly, in what they say about the loneliness, and the extreme steepness and difficulty of the road, the falsehood is manifest. For they never took the trouble to learn that the Celts who live near the Rhone not on one or on two occasions only before Hannibal’s arrival but often, and not at any remote date but quite recently, had crossed the Alps with large armies and met the Romans in the field side by side with the Celts who inhabit the plain of the Po nor are they aware that there is a considerable population in the Alps themselves; but in entire ignorance of all this they tell us that some hero appeared and showed the road. The natural consequence is that they get into the same difficulties as tragic dramatists all of whom, to bring their dramas to a close, require a deus ex machina, as the data they choose on which to found their plots are false and contrary to reasonable probability. These writers are necessarily in the same strait and invent apparitions of heroes and gods, since the beginnings on which they build are false and improbable; for how is it possible to finish conformably to reason what has been begun in defiance of it?
Of course Hannibal did not act as these writers describe, but conducted his plans with sound practical sense. He had ascertained by careful inquiry the richness of the country into which he proposed to descend and the aversion of the people to the Romans, and for the difficulties of the route he employed as guides and pioneers natives of the country, who were about to take part in his adventure. On these points I can speak with some confidence as I have inquired about the circumstances from men present on the occasion and have personally inspected the country and made the passage of the Alps to learn for myself and see.
(Source: Polybius, The Histories, Vol.II, Book III, Loeb Classical Library)
Research-Selection for NovoScriptorium: Anastasius Philoponus