Accessible from the car park in the hamlet of Costa, following a short path, the park is located on the dominant hill of San Lorenzino where the fortifications (around which the original village of Orco developed) were built.

The park is made up of the remains of the early medieval Castrum, an oratory, old houses and the church of San Lorenzino, the best preserved and the most visible building of the whole complex. The first building that you encounter reaching the Park is the Oratory dedicated to Saint George, perhaps the first religious building used by the inhabitants of the area, later replaced by the church of San Lorenzino. Surrounded by vegetation, the presbytery and the altar of the Oratory are well visible, surrounded by what remains of the ancient houses. Further along the path stands the Church of San Lorenzino. The first church, which no longer exists, was of Romanesque origin dating back to the XI-XII century, and presented exposed stones on the facade.

The actual church was built during the XV century and presents a single nave, with roof beams and bell tower square. From the church you can walk up to the top of the hill where you can still see the remains of the massive stone tower of the early medieval Castrum, a watch tower used as strategic point for the transits. From here you can enjoy a splendid view over Cornei Valley and of Monte Cucco.