This volume presents a comprehensive, multidisciplinary study of the late Byzantine fort of Santo Niceto in Calabria, examining its structural evolution, architectural identity, and socio-economic role within the regional landscape. Abandoned during the mid-fifteenth century, the site offers an extraordinarily well-preserved record of medieval military and rural infrastructure, documenting over four centuries of continuous use. Through rigorous archaeological field surveys, stratigraphic analysis of standing masonry, and newly collated archival and numismatic evidence, the research delineates fourteen distinct construction phases. The findings trace the origins of the castrum back to the late tenth and early eleventh centuries as an imperial defensive refuge for local agrarian populations during Saracen raids and Norman advances. Far from being isolated, the site functioned as a pivotal administrative and economic node controlling vital agricultural lands, silk production, and coastal salt pans before changing geopolitical conditions precipitated its decline under Aragonese rule.