During work for the _Intervention of special maintenance for the conservation and enhancement of the celebrated relics below the main altar of the church of the Holy Martyrs Cantius, Cantianius and Cantianella, an underground space was discovered below the main altar. It contained human skeletal remains, which have been given a preliminary date of the 17th-18th century as attested by the date incised on the gravestone. The excavation and recovery of these remains led to the identification of two construction phases, the first dating to the 16th century, the second to the 18th century. The anthropological analysis of the skeletal remains and historical research made it possible to define the different phases of the crypt’s use. The chronology established by the investigation also clarified several phases of the religious structure that were previously unclear if not completely unknown.