Charles sent fresh messengers to Desiderius, and offered him 14,000 gold solidi, if he would make restitution. All was of no avail. When the messengers returned to Charles, he brought the whole matter before his dukes and chiefs, probably at the May diet, and an expedition into Italy was resolved upon for the autumn. The Frank army was summoned to meet at Geneva. One part of it Charles sent by the Mons Jovis, the St. Bernard; the other he conducted himself by the passes of Mont Cenis, the same route which Pipin had held in 754 and 756. When Charles reached the pass above Susa, he found it strongly fortified and valiantly defended by Desiderius in person, and his son, Adelchis. Here it is said the Franks were so long detained, being unable to break through the Lombard defence, that they were on the point of retiring, when a secret road was discovered to Charles, and their flank was turned. The result was a precipitate retreat of Desiderius to his fortified capital, Pavia, and of his son, Adelchis, to Verona. From that moment the chief struggle was concentred about these two cities. Other cities of Upper Italy, such as Turin, Ivrea, Vercelli, Novara, Piacenza, Milan, Parma, Tortona, and the maritime cities, with their castles, fell speedily into the hands of the Franks. Charles sat down before Pavia at the end of September or beginning of October, 773. That royal city of the Lombards, in the eighth century, was first among all the cities of Upper Italy, not only for its riches and magnificence, but for its military strength. Near the confluence of the Ticino and the Po, it was esteemed almost impregnable. It had resisted Odoacer, and Alboin required more than three years to take it, which he accomplished rather by famine than by force. Charles encamped with his army round it, and completely enclosed it with lines and trenches. He sent for the queen Hildegarde and her children. He made an attempt to take Verona, but found it too strong for anything short of a regular siege, defended, as it was, by the most valiant Adelchis. However, the widowed queen Gilberga, with her children, who were therein, surrendered themselves to him. They disappear henceforward from history, and are supposed to have been confined in Frank monasteries. Charles spent the feast of Christmas in the camp at Pavia. All we know of these months is the two words of Eginhard, that he spent them, “much employed”.(240) We may conclude that not only the siege of Pavia, but the settlement of the numerous cities in North Italy, which yielded to him, well occupied his time.