The ancient city of Nora was a Phoenician, Punic and Roman settlement rising on a peninsula in the south-western coast of Sardinia. Since 1990, the University of Padova has been carrying on an interdisciplinary research project of excavation, architectural analysis, historical reconstruction and cultural promotion of tourism in this site. The excavations allow us to increase our knowledge of Middle Imperial Roman urban planning and to get a better understanding of the whole city and its history; the restoration of excavated monuments using gravels with different colours helps more than 60,000 tourists every year to recognize the function of different areas. In spite of this, visitors experience difficulty in understanding a landscape of ruins with barely visible evidence. Thus, a complete virtual reconstruction of the ancient city has become essential. 3D models of the Phoenician and Roman settlement have been developed, reshaping archaeological plans produced in 25 years by Universities that work in the site. The main monuments of the Roman city and the major crossroads have been rendered in greater detail, using sample-based textures that give a photorealistic effect and implementing the models with furniture and decorations selected through reliable sources of information. 3D reconstructions are now available for tourist groups led by a guide in the Nora Virtual Tour: stereoscopic images have been rendered and uploaded in an app for mobile headsets that provides immersive virtual reality for the users. The guide controls the devices with a tablet using a Bluetooth connection: at the beginning of the visit, the tourists can view equirectangular panoramas of the ruins taken from a helicopter, then they are accompanied to hot-spots where the ancient monuments are shown in an evocative Roman reconstruction.