Canossa castle: the importance of a critic and aware plan of interventions for conservation and prevention of cultural heritage.

Fortified architecture is a widespread and peculiar typology in Italy as it represents an identifying element for communities and a reference point in the landscape. An imposing system of castles, dating back to the 11th century, characterises the area of Reggio Emilia, in the Emilia Romagna Region. Among these fortifications, Canossa Castle is an important and distinctive fortress. Built on the top of an isolated cliff, a particularly strategic and defensive point, it played a central role in medieval European history. For instance, it was the scene of the well-known reconciliation between Henry IV and Pope Gregory VII, which ended the Investiture Controversy in 1077. The current state of ruins of this fortress is due to both centuries of neglect and to recent incongruent interventions. Therefore, archival research, in-situ inspections and photogrammetric techniques were carried out on the case study of Canossa Castle, in order to analyse the numerous restoration yards that have followed one another on the fortress in the last century. Firstly, the lack of coordination between the different interventions emerged. Furthermore, it has been observed that the principles of restoration have been disregarded several times, with consequent damage to the archaeological remains. Therefore, the present study aims to underline the importance of a critical and aware intervention plan for the conservation and damage prevention of cultural heritage, considering the possible support of HBIM tools.