The complex of San Calocero is one of the most important late antique and Early Christian sites in north-western Italy. Nino Lamboglia began investigations here in the 1930s, and his were the first stratigraphic excavations to be carried out on a post-Classical context. Later, in the 1980s and 90s, the site was the object of a series of campaigns undertaken by the Archaeological Superintendency of Liguria, directed by Dr. Giuseppina Spadea, with Prof. Philippe Pergola directing in the field.
A large containing wall with “decreasing offsets” was uncovered, which recent studies date to the 3rd century B.C. A wall in which five arches open, partially reconstructed in the 1980s, dates to the 5th century. The interpretation of these structures remains uncertain.

Between the end of the 5th and the early 6th centuries A.D., a large basilica with three aisles was built reusing earlier walls. This is the only martyrs’ church in Liguria as it houses the remains of local martyr Calocero (in actual fact an imperial functionary from Brescia who was posted to Albenga), who probably fell during Diocletian’s persecutions. The church had significant liturgical furnishings of Byzantine type, with direct parallels at San Clemente in Rome, while the latest renewal of these elements took place in the 8th century, with prestigious Lombard elements, including the known inscription of abbas Marinaces, which seems to place the ecclesiastical complex under the aegis of the Benedictine order. The events surrounding the monastery in the early middle ages are less clear, when the saint’s relics were wholly or partly moved to the monastery at Civitate in Lombardy (9th century). The fortunes of the cult site revived in the 13th century culminating in the establishment of an important convent at the end of the 14th century, later definitively abandoned in 1593.

The 2014 excavations, aimed at answering a number of questions that were left unresolved by the unexpected interruption of the investigation in the 1980s. Work thus concentrated on two sondages: one placed in front of the façade of the late antique church and the other on the upper terrace of the convent, in the attempt to understand what lay around the religious complex.

However, the early medieval stratigraphy was not intercepted because a cobblestone floor, probably put down in the 14th century, had caused the area to be levelled with the consequent removal of a large amount of terrain. The excavation will continue in this sector as narrow walls, which appear joined at 90°, and certainly relate to an earlier phase (imperial?) were seen below the earliest tombs.

The upper sondage revealed evidence of interesting traces of the late medieval quarry which, from the late 1300s, was used in the construction of the convent or for its restructuring not long afterwards. Another small sondage on the upper terrace remains to be completed in 2015, when a sondage should also be opened in the main nave, in the hope that the early medieval stratigraphy is preserved there.