The source of the Ticino is in Switzerland. Its main source is at the top of the Bedretto valley, at Passo di Novena, at an altitude of around 2480 metres. Once it leaves the Verbano basin near Sesto Calende (VA) the Ticino flows through the whole of the Po plains including Pavia, carving out a deep river bed, before flowing into the Po River at Ponte della Becca (PV).