Aisled Tetraconch: A Reconsideration of the Architectural Form in the East and in the West (5th and 6th Centuries)

Aisled tetraconchs, a common Early Christian architectural type, are attested throughout the Mediterranean (Italy, Balkans, Asia Minor, Syria, and Egypt). However, in the Northern Balkans it acquires a specific variation without eastern ambulatory. This group is represented by the basilicas in Lychnidos, Lin, Justiniana Prima, and Perushtitsa. A similar plan is found in Resafa (St. Sergius basilica), which was under the jurisdiction of the Patriarchate of Antioch, territory with the biggest concentration of the double-shell tetraconchs. Both Syrian and Balkan monuments have an accentuated eastern vector, although it is created with opposite planimetrical features. While the Balkan layouts stress the apse as the focal point of the interior, preventing the circumambulation of the altar, most of the Syrian churches have projecting chancels elongating the east-west axis (cf. Seleucia Pieria, Apamea, Amida). Another significant difference concerns the absence of narthex in Eastern tetraconchs, while in the Balkans it played a great role adjoining the pastoforia. In this context, Resafa seems to represent a parallel and not a prototype for the Balkan churches. The earliest known aisled tetraconch, San Lorenzo in Milan, has narthex and atrium, similarly to the complexes in Ohrid. However, it represents a perfectly centralized space that provides no basis for establishing a direct link with Balkan monuments. Balkan tetraconch proves to be the regional phenomenon based on a local model. The church in Hadrian’s Library in Athens bears a striking resemblance to the aforementioned churches, displaying all of their characteristic features: the absence of the eastern ambulatory, entrances on the sides of the apse, a narthex with annexes, and an atrium. Built in the city’s cultural center, it stated the importance of Christianity and could have served as an appropriate model for new centers of devotion. (The research is supported by the Russian Science Foundation, project 25-18-00656).