The most important mountainous area is the Alpine zone including the Lepontine and Rhaetian Alps (Piz Bernina, 4,020 m), the Bergamo Alps, the Ortler Alps and the Adamello massif. It is followed by the Alpine foothills zone Prealpi, the main peaks of which are the Grigna Group (2,410 m), Resegone (1,875 m), and Presolana (2,521 m).