Displaying Rituals: Simulating Potential Routes of the navigium Isidis Procession

The impact of religious rituals on city economies remains a topic minimally considered within Roman studies. The navigium Isidis procession at Ostia, which celebrated the opening of the spring shipping season, is used as a case study to question the ritual’s socio-economic implications during the late second century ad. This article introduces a new approach that simulates possible processional routes from the Egyptian temple of Serapis to the seafront or river harbour by considering the influence of spectatorship on the procession’s route selection. Visualization of potential movement routes provides new insight into this ritual’s various forms of economic engagement based upon its passage past different urban spaces and social groups within the city, bringing attention to the connection between urban movement dynamics and ritual visibility.