We know very about an early walled enclosure protecting Nicosia since Byzantine times. Later Henry I in 1211 built a castle to defend the city. Peter I started a complete city wall surrounding the city in 1368 and Peter I completed it in 1380. Janus I accomplished further works in 1426, and others were planned in 1450 following Nicholas V decision. In 1565, Giulio Savorgnano and Francesco Barbaro designed the new city walls demolishing the older ones. The paper analyses the case study of Nicosia, interpreting the ‘medievalisation’ process, in continuity between the Conzenian approach (Whitehand, 2012) and the Italian School of Urban Morphology (Marzot, 2002), (Maretto, 2013). The theory should cover in a more analytical manner what Muratori called ‘medievalisation’ (Muratori, 1959), (Caniggia, 1976) a term generically describing the transformation of urban routes occurring during the Middle Ages. The paper analyses the diachronic changes of routes in the city of Nicosia, Cyprus, and other multi-scalar occurrences of the attraction phenomenon (Charalambous, Geddes, 2015) applying attractors and repellers, already used in archaeological studies to interpret such changes. Only few routes change by attraction as revealed by the inflection analysis, other routes are instead bifurcated. The attractor causes the diachronic deformations of routes by pulling them away from their configuration, while the 'repeller' acts in the opposite direction. It is possible, therefore, to trace the path of the medieval walls of Nicosia, now disappeared, using the inflection analysis of urban routes, inferring the attractors and the diving lines. The Venetian city wall, determining a new dividing line and new gates acting as point attractors, can be analysed with the same methodology. The openings through those walls introduced in modern times, also seem to follow the very same morphological rules.