ISO 3166-2:IT is an ISO standard which defines geocodes: it is the subset of ISO 3166-2 which applies to Italy. It covers 110 provinces (Aosta Valley is a region, but considered as province). Each province has a 2-letter code, that is also used for car signs. Together with the ISO 3166-1 code IT for Italy they form the ISO 3166-2 codes.
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