On site archaeological museums : types of protection

The decision to preserve, in their original context, even the most fragile artefacts, such as floor and wall coverings and to exhibit the delicate stratigraphic or clay manufactures, has favoured the spread of archaeological museums in situ, by interventions aimed at the preservation of archaeological remains. Archaeological museums represent a particular typology capable of relating history through its ruins. Therefore, it is not a museum having typological and functional characteristics that answer to codified museum-graphical and display rules . The arrangement and the public opening of the archaeological sites in recent years have been the object of discussions, debates and interdisciplinary collaborations. Making an archaeological site a museum means ensuring its preservation, valorizing it in its context, protecting it and, at the same time, creating the best conditions for its use by the community. Today it’s possible to distinguish different approaches in different countries dictated by different environmental and climatic conditions and by the specific characteristics of each site. The approach differs even for its historical period and the different local interpretation of the remains of that period. This study aims to develop a classification of the types of protection for archaeological sites. In particular, such classification will distinguish the various types of protection according to: its form (complete and partial closure of the site), structure, techniques, materials used, and the degree of control of climatic conditions. It is this last point which will result to be the most complex. The aim of the study is that of understanding the more or less effectiveness of the solution in some emblematic interventions concerning conditions of comfort as in concern to the protection of the finds from weather (sun, rain, etc...). In this sense, an example is represented by the archaeological site of Villa del Casale in Piazza Armerina in Sicily (Fig. 2): its cover in translucent material, built in 1950, has caused a greenhouse effect and phenomena of condensation, with consequent damages to the mosaics present in it