Abstract: The Large Substructure is a large arched building on two floors, which, for its dimension and topographical prominence, represents one of the most noticeable archaeological remains of the ancient Roman municipium of Ocriculum, Umbria.
Despite the huge dimensions and the undeniable architectonic prominence of the Large Substructure, this monument is little known and has only been scarcely documented in drawings. These, however, do not provide insights into the function of the building and they have not been part of wider archaeological research on the monument. This research arises from the urge to fill this gap: the paper proposes a reconstruction of the Large Substructure in plan, section and elevation making use of existent drawings, new surveys and three-dimensional reconstructions. In addition to this, it provides a possible temporal framework for the building. From the analysis of the building technique and from using chronological references and individual comparisons with known monuments, the paper suggests to date the building to the second quarter of the 1st century BC. Furthermore, it proposes that the Substructures were one of the first interventions on the landscape after the relocation of the pre-Roman town to the plain below after the Social War of 90 BC. Finally, the study advances some hypothesis regarding the function of the Large Substructure and its spaces. Comparisons with other substructures in central Italy suggest that the Large Substructure constituted a monumental platform for a sanctuary. Regarding the function of the rooms of the substructure, it is possible that the rooms were used for commercial purposes or as a market.
My research represents the first scientific and comprehensive study of the Large Substructure of Ocriculum and illuminates the critical role of the building within the city and within the late Republican terraced buildings of central Italy.