You'll reach Piana from Ajaccio via the coastal highway D81. It is not very far but the highway winds around and over a lot of bays and passes. Shortly before Porto you have to go through the Calenche. The road is VERY narrow, and since the Calenche is a major tourist attraction lots of coaches use it. So it can take up to an hour to drive the 5km between Piana and Porto! Again, you might want to start early. The various trailheads are all on this road.
From Bastia you need to take RN 193. At Francardo you turn right onto D84 which will lead you through the famous gorge of Scala Sta. Regina. On your right hand side you will soon see Monte Cinto and Paglia Orba before you head upwards to the pass of Col de Vergio (1477m). From here you can already see Porto as well as Capo d'Orto though the actual drive will take you about an hour due to the winding narrow road.
Altitude gain: 900m
Duration: 3h 45min
Trailhead: Sports field northeast of Piana, close to D81
From the sports field follow the Val de Riviere de Piazza Moninca. After some 30 min the trail starts winding up the slope to the left until it levels out at Piazza Moninca. From there you hike downwards to Foce d'Ortu. Here the trail towards Capu d'Orto leaves to the left while the trail tu Capu di u Vitullu turns to the right and ascends steeply towards a shoulder from which you get a perfect view at both mountains.
From this point you wonder how you can get to the summit without scaling a vertical 300m wall but the trail slowly winds around the summit. In fact you do the complete 360° circle until you get to the final scramble which is easy but wich requires sure footing. At the end you are rewarded by a very nice view down to Les Calenche and to Capu d'Ortu just a little to the nrtheast.
Hiking gear is sufficient. Bring warm clothes because of the gusty winds.