Inside this complex framework, the aim of this study is to develop an empirical frequency-damage relationship, obtained by means of detailed local studies, which could be used as a judgement tool for flood mitigation improvements in small and strongly urbanised drainage areas. The urban area of Palermo (Italy) has been selected as a case study. When analysing urban areas, particular attention must be paid to the presence of monuments and other estates having a cultural or artistic significance. This kind of analysis is very important in countries such as Italy, full of architectural, archaeological, artistic and cultural sites, which are protected by laws ruling their retrieval, safeguard, preservation and exploitation. Ac-cording to the specific local contexts, the issue requires therefore specific analyses and methodological arrangements.