The St. Donato Cathedral in Arezzo. Digital reconstruction of a completely lost architecture

Abstract: 3D modelling tools allow to reconstruct what is not clear to the eyes. This simple and short phrase is quite obvious, but when it meets lost architectures it becomes the key vault of a complex puzzle made of evidences, knowledge, reading strategies and later communication strategies. In the research presented here, the case study of the St. Donato Cathedral in Arezzo, becomes the occasion for analysing a full digital reconstruction process, its adaptation to virtual interactive usage and how this process can bring back useful information on the ruins that today are the last traces of its existence. The St. Donato Cathedral was the core of an ancient and independent citadel out of the Arezzo’s walls. A settlement developed starting from the VIII century over previous Etrurian and Roman remains. It has been completely demolished in the XVI century for its political misalignment in front of the Cosimo de Medici’s domination strategies. Only few remains of the citadel plot are now visible in place. Significant traces of these cathedral walls were never be found during the archaeological investigations, but a various set of representations documents its main aspects. These representations go from very detailed and pictorial images to schematic sculpted items, to plan drawing. Using an accurate and articulated digital reconstruction project a complete 3D digital model is produced out of all the possible traces. The process will be described in all its key passages, from the digital survey of the area, to the definition of architectural elements. An interactive model of the cathedral will be presented in first release. Beyond the common features for this kind of models it will have two specific peculiarities: the indication of the level of liability of each part and the system of references used to guide the process.