You can reach the trailhead at Pietra Longa by car. Take SS125 north from Tortoli or south from Baunei and at km 153 turn into a side road heading east and down towards Pietra Longa. There are parking lots and a restaurant near the rock.
Altitude Gain: 730m
Difficulty: Exposed Scramble along the southwestern ridge
Trailhead: Pietra Longa on the coast
By far the more interesting of the two ascent routes, the trail from Pietra Longa winds through dense macchia undergrowth. It starts at the upper parking lot near the rock, right behind a shed on the left hand side of the lot. It traverses a slope and later descends into the plain between Punta Giradili and Punta Argennas. Some 45min after the start of the trail and after having crossed the plain you cross a creek. Some 200m behind the creek turn left to climb the slope towards the eastern edge of Punta Giradili. (This is the place we missed so pay attention!).
The trail first turns far north before returning along an upper slope and heading directly for the base of the vertical south face of Punta Giradili. From here follow a wide ledge between the south face and the valley. The trail turns further west and crosses a gravel slope, heading for a sheperd's shed, the Ovile dus Piggius.
200m after the shed turn right and climb trail less towards the summit of Punta Giradili. In some places the blue arrows can still be seen but most of the time you have to climb a karst plateau. Try to keep in the places where there is no macchia undergrowth. Though the karst rocks are not easy to hike, they are much better than macchia or even meadows (in which the same kind of rocks are hidden!).
Normal hiking gear is sufficient. Long pants are a good idea against the macchia.