Castellet-en-LuberonCastellet-en-Luberon, known simply as Castellet until 2018, is a commune in the Vaucluse department in the Provence-Alpes-Côte d'Azur region in Southeastern France. As of 2023, the population of the commune was 113.GeographyThe river Calavon forms all of the commune's northern border.