Since 2001 Nonantola has been at the center of an important archaeological research project which has made it possible to acquire much information on one of the most important settlement structures of the Italian Middle Ages: the monastery of San Silvestro, its village and the surrounding area. The fifth volume relating to this project concerns the results of the excavations carried out in one of the central squares of the historic center of Nonantola: Piazza Liberazione. This place had already been the subject of limited archaeological surveys in 2004 from which a portion of the church of San Lorenzo and the relevant cemetery had emerged. In the summer of 2015 the Municipal Administration, as part of an urban redevelopment project co-financed by the Emilia-Romagna Region that involved the historic center of Nonantola, started the renovation of the square. This intervention allowed the Ca 'Foscari University of Venice, under the scientific direction of Prof. Sauro Gelichi, in co-direction with the Superintendence of Archeology, Fine Arts and Landscape for the metropolitan city of Bologna and the provinces of Modena, Reggio Emilia and Ferrara, to carry out an overall investigation with the exploration of extensive excavation areas. It was thus possible to write another unprecedented page in the history of this place, which acquires even more meaning and value when compared with that of the great monastery. The foundations of the church of San Lorenzo have been brought to light, two construction phases of which have been documented (XNUMXth-XNUMXth century and XNUMXth-XNUMXth century) with the burials of the surrounding cemetery area. Going beyond the confines of the cult building - and going deeper - traces of the oldest settlement emerged, even prior to the foundation of San Lorenzo. In fact, the most ancient phases referable to the inhabited area of the IX-X century are attested by wooden structures with residential and artisan functions in the eastern sector, while the western area was affected by wooden structures connected to a defensive moat, hypothetical traces of the first defenses of castrum medieval. Following the defunctionalization of the church of San Lorenzo, at the end of the Middle Ages, the entire area explored was destined to be a market square with a brick and cobblestone pavement and brick pillars for housing wooden sheds. The volume collects the data relating to the excavation sequence, accompanied by the results derived from the analysis of the various types of archaeological finds collected and relevant to the various chronological periods attested.