Shifting point-attractors : the central-symmetric flexi of via Flaminia and via Clodia near pons Milvius, Rome

Recent urban morphology studies consider urban tissues as living organisms changing in time (Strappa, Carlotti, and Camiz, 2016), moreover even roads may be considered as organisms, and their diachronic deformations have been recently interpreted by the theory of attractors (Camiz, 2018). This paper analyses the fl exi on either side of the river Tevere along via Clodia and via Flaminia near Pons Milvius in Rome, and interprets them as the effect of the shifted position of a point attractor. The censor Gaius Flaminius Nepos established via Flaminia in 220 BC (Messineo and Carbonara, 1992), the via Clodia, running along an earlier Etruscan route, was instead paved in 225 BC. The pons Milvius, also known as pons Mollis, connecting the two sides of the river, was built by M. Aemilius Scaurus in 109 BC (Messineo and Calci, 1991), even though an earlier structure in wood is mentioned as early as 207 BC (Palombi, 2019). A fl exus occurs along both the rectilinear paths of the two streets, following a central-symmetry. This central-symmetric confi guration led to the reconnaissance of a differed attraction pattern within the trajectory of the road that we interpreted as the result of the modifi cation of the ramps of the bridge occurred after the foundation. The cross comparison of documents, iconographic and cadastral sources together with archaeological evidence lead to the confi rmation of the hypothesis, showing that the deformation and the consequent urban layering (Strappa, 2018) happened after the demolition of the lateral ramps in two distinct phases. The ramp on the south side was demolished by Maxentius before the battle of Ponte Milvio, held on October 28th 312 AD, the northern ramp was instead demolished during the bridge’s restoration works accomplished by Giuseppe Valadier in 1805.