The reasoning behind the renaming of the Naples to Canosa section is unclear, however an urban legend was formed in which, due to the high accident rate of the section, it was renamed to dispel the bad fortune brought on by the number 17, which signifies bad luck in Italy.[3]
Until then the A16 numbering was used by the motorway section that connected Rome to Civitavecchia which, as a consequence, took on the new A12 numbering. After being decommissioned, A17 numbering was never used for any other Italian motorway.[3]