There's a public road from Claro to Maruso (1049 m); the locals like to climb the summit from this place.
From Val Calanca, another starting point is Landarenca at 1280 m (bus to Selma, cableway to Landarenca).
An unusual and quite wild access is from Valle Cresciano - Alpe di Simidi - Pian Belasc - P. 2558. Nice for a swift descent in early summer, if there's snow left.
This is only for the very seasoned skiers, as the final slope is extremely steep and exposed in direction southeast. It's rarely done. Crampons and iceaxe necessary.