Hannibal outmaneuvered the natives who had tried to prevent his crossing, then evaded a Roman force marching from the Mediterranean coast by turning inland up the valley of the Rhône. His exact route over the Alps has been the source of scholarly dispute ever since (Polybius, the surviving ancient account closest in time to Hannibal's campaign, reports that the route was already debated). The most influential modern theories favor either a march up the valley of the Drôme and a crossing of the main range to the south of the modern highway over the Col de Montgenèvre or a march farther north up the valleys of the Isère and Arc crossing the main range near the present Col de Mont Cenis or the Little St Bernard Pass. Recent numismatic evidence suggests that Hannibal's army may have passed within sight of the Matterhorn. Stanford geoarchaeologist Patrick Hunt argues that Hannibal took the Col de Clapier mountain pass, claiming the Clapier most accurately met ancient depictions of the route: wide view of Italy, pockets of year-round snow, and a large campground. Other scholars have doubts, proposing that Hannibal took the easier route across Petit Mount Cenis. Hunt responds to this by proposing that Hannibal's Celtic guides purposefully misguided the Carthaginian general.