 Hello everybody, I'm Elico Petruzzi, I work in the Department of Architecture and Urban Planning of the University of Sasserie in in Sardinia and according to the theme of this conference that is Building Bridges, I would like to develop on one side the material and symbolic meaning of the Roman Bridge of the Colonia Julia Turi's Libisonis that was founded by Caesar in the around the half of the first century before Christ in North Sardinia and a town that has grown seamlessly up to the present city of Porto Torres and on the other side, I'll talk about the bridges between archaeological investigation, digital data elaboration and protection and planning tools processed in recent years in this town. The bridge that you can see is an important monument for the understanding of the topographical transformation of the city, the territorial structures and the road system of ancient modern and contemporary Sardinia. Indeed, since its construction in the period of the Imperius Tiberius, it was the only way to overcome the main waterway of this area until a few years ago. The construction of a railway and another one of the Highway Bridge north of the Roman Bridge, now they prevent the view of the ancient monument from the sea and exemplifies the devastation of this area and the lack or better an absence of a strategy in the archaeological heritage protection. The Roman monument, the bridge, represents in some way a symbol of the meaning of archaeology itself in contemporary Sardinia. It represents potentialities and contradictions keeping together two shores of the river. They are very close from a geographical point of view but also far from a landscape point of view. If we consider the landscape as defined by the European Landscape Convention apart of the territory as well as perceived by the people who inhabited. On the one hand, there is a highly polluted area, the industrial part, result of the failure of the industrial project and the consequent economic and social decline of the local community and on the other hand, the archaeological park, the center of the ancient city, yet largely to be investigated, luckily saved from industrialization and building speculation with important monumental evidences. The modern town represents, despite its limited proportions, an area of big interest interest for Sardinia and Mediterranean history and a particularly favorable context for the experimentation of functional tools for protection and urban planning. This area allows to test methodologies and tools in heterogeneous contexts, peripheral areas, which were subjected to the devastating action related to the realization of an industrial area, or the city center where the historic city has grown in a really complex stratigraphic way. Over the past 10 years, the archaeological superintendents and the Department of Architecture and Urban Planning have been carried out several archaeological investigations in the urban and peyurban areas and elaborated digital tools for systematization, standardization and communication of the archaeological data. The analysis of data acquired in planned and rescue investigation has allowed to elaborate a series of new hypotheses of urban transformation of the city from the first century before Christ until late antiquity. The excavations carry out at the mouth of the river in the Roman bridge area confirm the existence of a pre-colonial settlement functional to the river harbour and for the exploitation of the agricultural and mining resources of northwestern Sardinia. Until the first century before Christ, in this part of the island, there wasn't any kind of a urban settlement, unlike the southern part where the urban phenomenon was already known for eight centuries after the Phoenician colonization. The foundation of the city with its infrastructures as the bridge, the aqueduct, and the public buildings, represents the most important intervention for the Roman territorial structure of an area still strongly linked to the traditional indigenous system of exploitation. The main road of the northern Roman system, the Attibula Sulci, passed along the city through the bridge and defined the vast western necropolis investigated several times in recent years. The construction of the bridge linked to environmental needs and regional road system determines the orientation of the city's blocks and roads and affects subsequent transformation of the urban body. It has been hypothesized that the construction of the bridge has progressively limited the port activities originally carried out at the mouth of the river and determined from the second of the second century after Christ, the construction of a second port and the extension of the inhabited area beyond the original boundaries of the colony. The translation of the harbour seems to involve a reorganization of the urban and viability structures. The crossroad found in a recent excavation still frame the second half of the second century seems to manifest this phenomenon. The presence of this intersection, which breaks up the regular planimetric schemes that tested in other areas of the city, underpins the need of urban planning towards forced passages, first of all the gates of the city. Latest excavations are led to hypothesizing the absence of a city wall circuit that will be realized in the half of the third century, the existence of a monumental door on the eastern side of the city, a monumentalization of the colonists limit that had its opposite in the bridge on the western side. One of the titles comprised about the development of a road axis that passes through the town from the monumental door to the bridge across the urban area seems to be the colony of Ariminum, funded in 268 before Christ, but monumentalized in the time of August with the creation of monumental doorways. The planimetry and the more morphological context of the two cities appear to have considerable affinities. To the urban expansion of the first century contrasts the progressive contraction of the inhabited area in the fourth in the fifth century, which will result in a situation of absence of the urban plan at the solution of the city until the birth of two distinct urban poles that will remain substantially in the same shape until the recomposition of a urban body in the 19th century. Archaeological research and topographic reconstruction have been consistently used over the past ten years for the design of plans and implementation of digital tools useful for heritage protection and urban planning that can be summarized in three fundamental steps. First, the elaboration of the historical cultural heritage plain of the urban area carried out in the context of the adaptation of the urban plan to the regional landscape plan of Sardinia, the implementation of the archaeological information system of Porto Torres and finally the experimentation of the parameters of the National Archaeological Information System, CITAN, in the context of the national project creation and activation of the Sardinian pole of the National Computer Network for the collective construction of the web GIS of the archaeological heritage of Italy. Within the municipal urban plan, the remarkable level of knowledge has allowed to define the limits of the ancient city in the maximum reach achieved by the inhabited and the cemetery areas, the planimetric relationship with the contemporary urban body, the general lines of topographic evolution and the delimitation of different functional areas. The consequent elaboration of the archaeological potential map functional for a predictive analysis of the distribution and intensity of archaeological deposits has been the basis for the construction of the actual urban planning tool, the archaeological protection map which defined areas of prescriptions for a sustainable developing of the city. The need for advancement towards a digital instrument more specifically aimed at the activities of heritage protection as resulted in the implementation of the Porto Torres Archaeological Information System designed for greater accessibility and functionality of the archaeological superintendents, public institutions and individuals and broader possibilities for interrelation of data already processed and imposition of different entities. The third project was the Sardinian pole and the goal of this project of the National Network for the construction of the GIS was to archaeological heritage was to satisfy the need of coordination between the archaeological researches and targeted to achieve a system of relations, standards and best practices for the involvement of what are called big producers of data through the implementation of the web GIS site of research protection management and use of the Italian archaeological heritage. The practical perspective in using this system are related to the possibility of using a geo-referenced archive of archaeological data with those of an administrative nature and to communicate with other information systems and existing databases through web applications. The goal is to reach the effective sharing within the public entities involved superintendents, university regions, local government and municipalities of the results of all past, present and future investigations aimed to know and understand historic territories and cities. Despite the stall phase of the SITAN project at a national level, the work proceeds locally focusing the analysis and experimentation on the acquisition of archaeological data coming from the most recent excavation conducted along the urban coastline, the most sensitive area to the urban transformations in the immediate immediate future through the geo-referenced planimetric and scale representation of all the archaeological knowledge acquired and open to the implementation of new data. Porto Torrez has been in the last decade laboratory for the design, elaboration and use of digital tools for archaeological information management as a base for planning urban transformations. We are still working to build new bridges between the different branches of archaeological research and urban planning methodologies as instruments for overcoming disciplinary fences and for the acquisition of archaeology among the real interest of citizenship.