Le Thor is a commune in the Vaucluse department in the Provence-Alpes-Côte d'Azur region in Southeastern France. In 2021, it had a population of 8,858. It has an attractive Romanesque church, Notre-Dame-du-Lac, an 11th-century castle in ruins, the Château de Thouzon, as well as an Urgonian Limestone cave, the Grottes de Thouzon, accessible for visits to the public.