Les rehaussements du Decumanus dans le contexte des « quartiers » occidentaux d'Ostie

The western section of the decumanus and the neighbourhoods it crosses, as we can see them today, offer a landscape deeply marked by the reworking and restoration work carried out following the excavations carried out by Guido Calza in 1938-1942. These works are part of the staging that was carried out at the time in response to the imperialist ideology of the Mussolini regime, which sought to highlight the "golden age" of the first colony of Rome, which was attributed to the 2nd century AD. However, this kind of scenography conceals from the layman's eye the complexity of the evolution of the urban fabric of Ostia.

To date, only the didactic area below the Domus sul decumano (III, II, 3) bears witness to this complexity. This survey, carried out after the Second World War by Italo Gismondi, shows that these "districts" have gone through several major phases since their creation during the Republican period. These phases can be clearly seen in the successive raising of the decumanus and the gradual raising of the level of the peripheral buildings. These increases in levels were accompanied by a continuous widening of the street, which had significant repercussions on the urban fabric of the area. Likewise, these transformations affected the roads leading to this axis, such as the Cardo degli Aurighi.

Up to now, the problems related to the raising of the levels have been mainly dealt with on individual plots of land. This approach presupposes that the stratigraphy of a single plot accurately reflects the stratigraphy of the surrounding urban fabric. My paper aims to clarify these issues by avoiding this methodological bias. With this in mind, this reflection will focus on the space of the street and will be based on data collected since 1938. These include the documentation of ancient excavations preserved at the Parco Archeologico di Ostia Antica and the Archivio Centrale dello Stato, as well as the results of recent excavations, in particular the results of investigations carried out in the Tempio dei Fabri Navales (III, II, 1-2), the Schola del Traiano (IV, V, 15-16) and its annex, the Caseggiato delle Taberne Finestrate (IV, V, 18).

This documentation will allow me first of all to restore the archaeological landscape as it was before the remodelling carried out in 1938-42. I will then highlight the evolution of the urban fabric of these "quarters" between the 1st century BC and the 3rd century AD, using the heightening of the decumanus as a guiding thread. However, the transformations of this space cannot be understood in isolation from the buildings with which it interacted. I will illustrate the close link between these components of the urban fabric by presenting a longitudinal section of the plots of the Schola del Traiano and the Tempio dei Fabri Navales (III, II, 1-2), one opposite the other on either side of the decumanus. This dialectical approach between the road system and the built environment, which is new to Ostia, will shed new light on this area of the city and will be a new milestone in our knowledge of these "districts" after the publication of the proceedings of the symposium held at the Academia Belgica in 2014.