Legend has it that Saint Martin, bishop of Tours, having to return from Italy to his diocese, found himself blocked by the Lys torrent, which with its flood had overwhelmed the only footbridge. The devil proposed to him to solve the problem by building a solid bridge in a single night, but he demanded in exchange the soul of the first one to cross it. The saint accepted, but the next morning, by throwing a piece of bread at the other end of the bridge, he made sure that the first to cross it was a hungry little dog. The devil, furious, disappeared in the Lys between lightning and whiffs of sulphur, and the population was left with the bridge. The legend still constitutes one of the fundamental themes of the Pont-Saint-Martin carnival, which ends with the burning of the devil under the Roman bridge.