The volume, two years after the end of the last excavation campaign of 2021, presents for the first time a coordinated reading of the old and new data emerging from the research, with an interdisciplinary method, which combines the presentation of the excavation data, historical insights and scientific. The proposed result is the reconstruction of the genesis and evolution of the historical era of the site of the Piana di San Martino, of which six phases have now been identified, from the XNUMXth to the mid-XNUMXth century, with exceptional evidence of the presence of wooden buildings from the XNUMXth century to the middle ages. From late antique and Ostrogothic castrums, with significant comparisons with highland castrums, such as the nearby Sant'Antonino in Perti, founded on the fluid Gothic/Byzantine boundary, of which imposing defensive, residential and service wall structures remain, including two cisterns and significant artefacts, imported ceramic pottery, coins and monetary weights, after the partial demolition of some structures following the Greek-Gothic war, the archaeological evidence found attests that the site was structured in the early Middle Ages as a village and just after the year XNUMX as a centre. castrense d'altura of local lords of Lombard tradition, that castrum Poncianum cited by archival sources from the beginning of the XNUMXth century. The site assumed the function exclusively of a place of worship and funerary from the height of the Middle Ages to its disappearance due to the closure of the church of San Martino to worship, with loss of memory of the place from the 1990th century until its rediscovery around XNUMX thanks to reconnaissance by volunteers of the Pandora Association of Pianello. With the 2018-2021 research it was possible to reconstruct a stratigraphic matrix and elaborate phase and structure plans from scratch, relating old and new data, which made it possible for the first time to distinguish and give an extended reading of the phases of employment and related contexts. The systematic study of the data now allows us to place the site in the framework of the historical transformations that occurred over a wide span of centuries, until now little documented for the Piacenza area, in a territory, the Val Tidone, turned towards Piedmont due to contacts and cultural influences, Liguria and Piacenza and with evident links with the monastery of Bobbio and with the largest urban centers, such as Brescia, Pavia, Milan and with the court of Ravenna in the late ancient and early medieval periods. The site of the Piana di San Martino, declared to be of important archaeological interest, lies on a plateau in a suggestive landscape setting on the top of Monte San Martino. From the first surveys, a complex anthropic stratigraphy emerged, attesting to the presence of two discontinuous periods of frequentation: one from the Final Bronze Age to the second Iron Age, another which goes from the Late Antique age to the mid-XNUMXth century. The first investigations carried out from 2000 to 2012 on the stratigraphic deposit of the historical era brought to light notable movable artefacts and substantial remains of walls of buildings from late antiquity to the end of the XNUMXth century.