Le ultime fasi della monumentalizzazione del centro di Ostia tardoantica

Thanks to the optimal working conditions guaranteed by the Superintendency of Rome/ Ostia, since 2010 an international team of the “Ostia Forum Project”, directed by Axel Gering and financed by the Humboldt-Universität Berlin, had the chance to extend the archaeological fine-cleaning of antique plazas from the ‘Foro della statua eroica’ to the main Forum. The aim of the project is a complete documentation in 2-D-fotomosaics and 3-D-models based on high-tech provided by the German aerospace (DLR) and the Exzellenzcluster TOPOI Berlin (laser-scans & fotografic 3-D-modelling). So far, the Forum was excavated until 1924, but until today no detailled stone-plan of the Forum existed. The methods applied are ‘minimal-invasive’, that means, they include archeological fine-cleaning of all antique surfaces and trenches already exposed during the old excavations, geophysical prospections and additional limited sondages in areas of former refill in order to draw stratigraphical profiles. Our analysis of the Forum of Ostia so far is in two ways surprising: Instead of the unique hadrianic Forum proposed by the excavators of the 1920’ies we have found a completely new evidence of monumental flavian and trajanic predecessors on one hand and dominant late-antique building activities on the other. By simple ‘reexcavating’ the antique surface underneath modern vegetation-layers a lot of missed dating evidence came to light. This allowed us to understand the complex history of collapses, repairs and constant level-raises of the Forum’s buildings since augustean times. By reconstructing the partly lost pavements by their imprints in the cement-bedding and by comparing stratified finds we can date a complete rebuilding of the Forum Porticoes in the late fourth and first half of the fifth century, and – even more surprising – a last restoration of the secular and still monumental marble-buildings after a major earthquake which is recorded stratigrafically around 450 AD and which corresponds surprisingly with the seismic event(s) of the written sources of Ravenna and Rome in 442/443 AD. Partly we have found evidence of irreversible destructions, like the Roma- and Augustus-temple and the circular monument in the centre of the Forum, but Ostia’s late-antique Forum obviously still was important enough for a last “post-vandalic” repair. In the south of The Forum we can attest predominantly commercial functions as the nearby macellum, the ‘Foro della Statua eroica’, where we had found evidence of a similar earthquake-destruction of the lateral porticoes around 450 AD and their complete rebuilding as late as in the second half of the 5th century. After centuries of robbing-activities and an almost complete neglection in research since, the Forum of Ostia can regain a prominent position for future research due to the first detailed documentation of finds-contexts and stratigraphical sequences on one hand and its ‘unusual’ late monumental restoration on the other: This is verified by the unique insight into the process of spolia-reuse for new pavements provided by our spolia-research, and the unique dating-evidence of statue-relocations of the 5th century in its northern half and of the previously undocumented pavements with graffiti and traces of late-antique every-day-use in its south, which were covered and preserved in situ until our excavations and survey-activities brought them to the light