Abstract
In this thesis, the oldest block called Castellaccia in the center of the historical district of Peccioli, small medieval city in Tuscany, is studied through the typology of the component buildings in the block. These buildings are divided into two types, 'casa a schiera' and 'casa in linea', and then classified by the number of 'cellura' to analyze the relationship between function and composition of the space. As another study, component buildings in the Castellaccia are investigated through the 'cadastre (1834)' and present surveyed drawings in order to clarify the transformational process of them since 1834.