ABSTRACT: The research documents a building of great complexity, the former Salt and Tobacco State Monopoly Warehouse, abandoned for more than 30 years and, for its location, part of the historical center of Mantua recently added to the UNESCO sites. The investigation of the architectural complex included geometrical survey, analysis of the materials, of their decay, of the building technique and of the structural condition. An important step of the project is the evaluation of the building evolution, resulting from the different building steps, uses and ownerships, carried out through the stratigraphic survey of the fronts and the archive research. The aim is to identify potential weakness and vulnerability of the complex.