In Cagliari, there's Via 29 Novembre, a street name unique to Sardinia. But how many Sardinians know what it refers to?

This is the question posed by the linguist Enzo Caffarelli , one of the leading Italian experts on onomastics, in an article published in “Lingua Italiana” , the magazine of the Treccani Italian Encyclopedia Institute .

The same, however, applies to other “odomini” (or rather “crodonimi”), or street names, which are identified with a specific date on the calendar and fix in toponymy historical events that represent crucial episodes in national and regional history, often forgotten.

There are many examples: for example, Via 31 Marzo in Palermo (the date of the Sicilian Vespers of 1282), Via 12 Ottobre in Genoa (in commemoration of the discovery of America), Via 4 Marzo in Turin (to celebrate the promulgation of the Albertine Statute in 1848). And again: Via 20 Settembre in Rome (in commemoration of the Breach of Porta Pia which in 1870 marked the end of the temporal power of the popes), Corso 22 Marzo in Milan (the last of the glorious Five Days during which the Austrians were expelled in 1848).

In Cagliari, as mentioned, there is Via 29 Novembre, which commemorates the day—in 1847—when the island renounced its autonomy to merge with the other states of the Kingdom of Savoy. A day that some Sardinians still call, however, "the betrayal of their homeland."

According to Caffarelli, students taking remedial exams—and studying history more generally—could benefit from a useful refresher course and find an equally useful learning method by learning why certain streets and squares in their city are named with certain odonyms.

This is true for local history – such as the case of Via 29 Novembre in Cagliari – but it is also true for national history, given that some key dates for Italy are repeated in numerous cities, from north to south.

Just think of March 16, 1978, the date of the kidnapping of Aldo Moro and the massacre of his escort in Via Fani, Rome, or August 2, 1980, the date of the attack on the Bologna station.