The Adamello range extends over the provinces of Trento and Brescia.
The western boundary of this massif is the border between the two provinces, which runs along the high crest, which starts at the Punta del Castellaccio, above the Passo del Tonale to the north, touches the Monte Fumo and Monte Re di Castello, and ends at the Ponte Caffaro, to the south. In the north, the boundary is the section running from the Corni di Lagoscuro and the Passo Presena, which descends into the Val di Genova up to Pinzolo. It then follows the more clearly defined eastern boundary, which crosses the Val Rendena and the Giudicarie Interiori and ends at Ponte Caffaro; this is where the short southern boundary of the range is located. Geologically, the range consists of intrusive volcanic rocks (quartziferous diorite, called tonalite or Adamello granite). The glacier system in the Adamello range is rather extensive: some of the glaciers are very large (the Vedretta del Mandron is the second largest cirque glacier in Italy) and are renowned glaciological research camps.