Mostly French - big surprise, I know. The most common other languages in France are the langue d'oïl, a Romance language with Norman, Francien, and Occitan influences, and the langue d'oc, another with Catalan and Provençal influences. In addition to these national languages of France, there are also various regional vernaculars that have maintained their particular characteristics: Alsatian in Alsace-Lorraine; Corsican of Corsica Basque in Aquitaine Breton spoke by the Bretons Franco-Provençal in Franche-Comté Monaco, among other places. So there is no shortage of things for people to speak about during their visit!