The archaeological investigation of the site of S. Stefano (Isola del Cantone, GE) is part of the “Medieval Archaeology in the upper Scrivia Valley” project run by the University of Turin’s department of history. The research, which began some years ago with the open-area excavation of the Roman and late antique rural settlement of Montessoro, aims to study the settlement and structures in the rural territories of the upper Scrivia valley between the late antique and late medieval periods. This settlement, situated between Genoa and the plain has never been systematically investigated and was chosen as a sample area for gathering data regarding the socio-economic, cultural, and environmental dynamics of the Ligurian Apennines in the period in question. The remains of the chapel dedicated to S.Stefano stand on a hillside terrace (380 m a.s.l.), occupied by a coppice, above the village of Isola del Cantone. The presence of this building can be associated with the road, which until the 1930s linked the Scrivia to the Val Borbera and to Tortona (in Piemonte). Surface surveys undertaken in diverse periods in the surrounding area revealed the presence of Roman rural settlements linked to the roads that were an alternative or subsidiaries to the _via_ _Postumia_ that linked Genoa with settlements on the plain. The chapel, part of the diocese of Tortona (AL), is mentioned for the first time in the account of a pastoral visit in 1600, which attests its dependence on the parish of Montessoro and documents its very poor state of preservation. In 1645 and 1658, the Bishop of Tortona visited the chapel again. The document states that in 1680, the rector of Isola, Giò Maria Deferrari, wrote a petition to lay claim to the chapel for the church of Isola and that in 1787 the bishop ordered the restoration of the roof, walls and altar, threatening interdiction if this work was not carried out. At the beginning of the 19th century, the chapel was still used for services and despite its very bad state of preservation, a fresco depicting S. Stefano, S. Lorenzo, and S. Giovanni Battista was still visible. In 1986, the ‘Centro Culturale di Isola del Cantone’ cleaned the site, removing a large part of the collapsed levels and obliterating what was later revealed to be the structure’s final building phase: a small single-apsed building, with a stone floor and brick-built altar. On the west side, the traces of two buried walls were identified outside the building. The apse wall, built of marlstone ashlar blocks, was dated to the 12th-13th century. As well as recovering pottery dating to between the 18th and 19th centuries, the excavation found a green stone Neolithic axe and a fragment of a Roman roof tile. Following these interventions, the local council consolidated the chapel walls, standing to a maximum height of 1.5 m, using cement. If on the one hand this preserved the structures from further decay, on the other it made it difficult to read the plan and stratigraphy. As the elements described so far are of considerable historical-archaeological interest, in 2014 a first excavation campaign took place. The investigation aimed to define the plan, evaluate the potential of the stratigraphy and date the site more precisely. An excavation area of 135 m2 was opened, which has begun to shed light on the building’s construction phases, probably dating to the 13th century, and which until it was reduced in size to become a chapel (between the 18th and 19th centuries) had been a larger structure. The discovery of burials outside the chapel suggests that until the modern period, it functioned as a parish church or a private chapel.

The 2015 campaign provided more information about the building’s history, documenting unknown elements regarding its chronology, development of its plan and original function. The small single-apsed building kept the same alignment throughout its life (apse facing east), but underwent various alterations to its plan. The first two phases (11th-12th century) are only partially known, as only attested by fragmentary parts of the apse and walls (phase 1) and by the apse and several stretches of the nave (phase 2). The latter, was characterised by a construction technique that used squared marly-limestone blocks arranged in regular courses. In the 13th century, the structure was rebuilt, probably by a specialist workforce (magistri Antelami), using stone blocks that were squared and flattened on the outer face, arranged in regular courses. Although the apse, built directly on top of the earlier one, is standing because it remained in use until the final construction phase, excavation was necessary to uncover most of the nave’s perimeter walls. The church underwent substantial rebuilding on two more occasions: in the late medieval period, when the nave was completely rebuilt, and in the 17th century, with the drastic reduction in size of the nave. The excavations led to the identification of 40 graves, 39 of which single burials, while one (t.34) contained three individuals all buried at the same time. It is possible that the skeletons in what have been identified as two separate graves (t. 40, t.41) were buried at the same time. A total of 40 individuals were found, 26 adults, 11 infants and 3 adolescents. The 26 adults, of which 15 male, 9 female and 2 indeterminate, include individuals from all adult ages: 4 young adults, 3 mature, 2 elderly and 5 indeterminate. Some preliminary considerations can be made about the distribution by sex and age of the individuals. Firstly, burials of sub-adults and females are always present in the 9th and 15th-16th centuries, while male individuals, in addition to infants, appear between the 14th and 15th centuries. Both sexes only appear in the 13th century, which corresponds with the phase having the largest number of depositions (14 individuals). Tomb13 is an interesting case, an “anomolous” burial with an individual (an elderly female) placed with the head to the north in a prone position, the arms folded below the torso and the legs bent. The excavations at the site of S. Stefano are of fundamental importance for the understanding of territorial and population structure in the northern Scrivia valley between the late medieval and modern periods.