Piz Blas is a mountain in the Lepontine Alps , located on the border between the cantons of Graubünden and Ticino . At 3,019 metres above sea level, Piz Blas is the highest mountain of Val Cadlimo (Ticino), a valley drained by the Reno da Medel, a tributary of the Rhine . On its northern side (Graubünden), it overlooks the valleys of Lake Curnera and Lake Nalps, both drained by tributaries of the Rhine.