This fourth campaign of archaeological investigations concentrated on the areas already partially excavated in 2004. The aim was to complete and refine the data collected before redevelopment began of the area in front of the church of S. Osvaldo, where the remains of structures CF8 and CF9 were found. Inside structure CF9, situated next to the church’s façade, excavations revealed, as expected, stratigraphy compatible with that uncovered previously. This comprised a quite recent layer of material from the restructuring of the area in front of the church and two substantial layers of collapse. Along the side next to the tower the organic remains of a wooden plank were uncovered, partially excavated in the preceding year, laying directly on natural. A few centimetres below the present surface level of the area in front of the church a walled structure on a N-S alignment was revealed below the façade. This can be identified as the continuation of the imposing eastern perimeter wall of the tower. As regards the investigations in CF8, two layers of collapse were uncovered to the south of which was a layer of very fine material, probably a dump relating to the restructuring of the church. Below the collapses, towards the north, a dry-stone structure emerged on an E-W alignment which covered an accumulation of earth and small to medium stones. Below this were layers of charcoal and red clay relating to a phase of burning. Also identified was a second level of stone slabs with circular cuts, perhaps used as supports for cooking pots. Excavations were also undertaken in corridor N in the area where the pavement was incomplete. these revealed the presence of a posthole, positioned against the wall. (Simonetta Minguzzi)