Dalla «Nuova Pianta» del Nolli al Catasto urbano Pio-Gregoriano: L'immagine di Roma all'epoca del Grand Tour

This essay presents an analysis of Rome's territory in the one hundred and fifty years leading to the breach of Porta Pia by utilizing the period's two most significant cartographic sources: the Nuova Pianta di Roma by Gian Battista Nolli, published an 1748 and the Pius-Gregorian cadastre, compiled between 1818 and 1824. Although initially drafted for different purposes these cartographies are strongly linked and share the need for exact metric measurements. The results presented in this study are an integral part of an ongoing project, promoted by CROMA, for the creation of an atlas of Modern and Contemporary Rome (Atlante di Roma). Its aim is to reconstruct the evolution of the city's historical environment by combining historical research and geographic information systems (GIS), thanks to multidisciplinary diachronic analyses made possible by the digitization of historical cartographic and thematic sources. © 2007 Università Roma Tre-CROMA.