In this paper an 1800's masonry tower is analyzed in order to assess its structural behaviour, its seismic vulnerability and to design the retrofitting. This paper details the consolidation of the masonry tower with the comparisation between the existing state and the retrofitted state. The heterogeneity of the soil has acted in a manner to determine the failures. The comparison demand versus capacity confirms the susceptibility of this type of building to extensive damage and possible collapse, which has been frequently observed. The analytical and numerical models adopted to interpret the experimental results have all confirmed that the first harmonic frequency of oscillation of the largest bell is very close to the first eigen frequency of the bell tower structure. The experimental analysis have shown that the retrofitted improved the seismic behaviour and the security level of the tower
