In Italy extreme cities and territories occur at the extremities of lagoons,coastlines,and river deltas,in hydraulically reclaimed and hydrogeologically instable areas,and those where the water supply network has been placed underground,channeled into piping,or removed altogether. These areas are now increasingly subject to natural calamities and extreme weather conditions,and the consequences of climate change and the fragility of the more and more impermeable and urbanized land surface are clearly evident. Isotropic territories are characterized by weak hierarchization of infrastructure and settlement. The metropolitan area of Venice,aptly described as a diffuse city(città diffusa),and other diffusely organized territories characterized by settlement dispersion are good examples of this phenomenon. This article reviews recent research at the University IUAV of Venice in a study on climate change and water forms,a project in which the profound relations between water networks,the geological nature of the terrain,forms of urbanization,and energy saving are tested out. The study of the territories of the Venetian metropolitan area provides a series of initial working hypotheses as to how the ongoing environmental emergency can become an opportunity for a development project of the city and the territory,capable of structuring its various parts differently.