Mergugno can be reached with a combination of post bus (up to Brissago) and taxi service. Alternatively, it is possible to move with your own vehicle, but it should be considered that from Cortaccio you will need to retrieve it.
From Mergugno, follow the signs for "Al Legn, Ghiridone" and start the long ascent to the hut. The trail is very well marked and the effort is richly rewarded by the charm of the sacred forest. Upon arrival at the Al Legn refuge (located about halfway along the route), begin to descend following the signs towards Cortaccio. You can go down on foot towards Piodina and return by bus or return to your vehicle using the taxi service.