Settlement Unit as constitutive part of the contemporary city. "Terre" in Southern Salento (Italy)

The morphogenesis of the city generally develops itself in discontinuous way. Recognizing the impossibility to think the city as a unitary form, for the complexity and the lack of homogeneity which characterize its form, the model of the city for parts, appears the most appropriate to interpretate its development. The settlement units of ended form is an urban part of an intermediate scale between that of architectural unit and that of urban organism, through which it is possible to define a model of city built as mosaic of single interventions, recognizable in its spatial, formal and functional identity. These models are referable to some paradigms of Italian urban culture that, starting from the idea of city for parts [1], introduced by the studies of A. Rossi and C. Aymonino in the school of Venice, are identified with the settlement unit of the district, with the idea of urban sod by F. Purini [2] and with the micro-urbanism of S. Holl’s urban projects. The rational nature of the settlement unit is related to an urban action of planned type. In this sense, it shows many similarities with some medieval models of settlement/housing, among which, one of the most interesting is that of “terre”, settlement and planned urban units that constitute the morphological episteme of the cities in southern Salento (Apulia, Italy).