An urban image in an urbanized landscape: measuring the visual impact of Tibur's amphitheater

Though infrequently used and largely superfluous, amphitheaters were often the most physically imposing and ideologically charged structures in a Roman city. The preponderance of extramural amphitheaters in Italy and their appearance in visual culture confirm they were potent markers of urban life and civic status. This paper contextualizes Tibur's imperial amphitheater within the Roman suburbium's persistent urban sprawl and villas, especially Hadrian's Villa, using a novel GIS visibility analysis. Its apparent size from various points in the surrounding landscape is quantified within empirical and qualitative scales developed for modern visual impact assessments. The results demonstrate the amphitheater's suburban location did more than integrate Tibur's extramural growth into the older urban center. It emphasized the city's urban appearance, even from long distances, and monumentalized alternate routes to the city used by the villa-owning elite, countering the ambiguous status of a liminal city that was both Rome's annex and an autonomous municipium.