In the first half of the 13th century, work began on the walls of the ancient village of Thatari. The enclosure had four gates (Gurusele, Santu Flasiu, Capu de Villa and Utzeri) arranged at the ends of two orthogonal axes and opened in the base of towers or in reinforced sections of the enclosure. Thirty-six crenellated towers as the curtain wall contributed together with the moat to make the work more fortified. The gradual demolition of the city walls, already badly scarred by time and no longer functional for centuries, ended in the late 19th century with the demolition of the 14th-century Aragonese castle. Only short visible sections survive today with a few towers along Corso Trinità, in the round tower street and in St. Anthony Square where the only tower with battlements can be seen. Coats of arms depicting the town tower, the shield of Genoa, and the fleur-de-lis, the symbol of a podesta family, are still visible in the stretch of Corso Trinità.
