One example of local canon (more of them could be find inside) is located near Monastir Ribat, exactly just couple of meters from entrance to fortress/museum.
Monastir Ribat
Erected in 181 (796), the Monastir Ribat was enlarged on the north side in the Aghlabid period, and on the south side during the Fatimid era in 355 (966). After works carried out at the time of the Hafsids, indicated by a commemorative plaque dated 828 (1424), the fortress expanded to a surface area of 4,200 sq m. Many consolidations as well as several polygonal and circular towers were added between the 11th and 13th / 17th and 19th centuries in order to accommodate pieces of artillery.
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