Southern Italy is generally thought to comprise the administrative regions that correspond to the geopolitical extent of the historical Kingdom of the Two Sicilies, starting from Abruzzo, Apulia, Basilicata, Campania, Calabria, Molise, and Sicily; because of this historical reason, and the fact that southern Italian dialects are spoken there as well, some also include the southernmost and easternmost parts of Lazio, (namely the districts of Frosinone, Sora, Cassino, Gaeta, Cittaducale, Formia and Amatrice) within the Mezzogiorno. The island of Sardinia, although being culturally, linguistically and historically less related to the aforementioned regions than any of them is to each other, is frequently included as part of the Mezzogiorno,[1][13] often for statistical and economical purposes.[14][13][15]