La morte-saison des amours

The Season for Love is a 1961 French comedy drama film directed by Pierre Kast and starring Françoise Arnoul, Daniel Gélin and Pierre Vaneck. The film's sets were designed by the art director Jacques Saulnier. New Wave in style, it was shot primarily on location around Chaux and Arbois and particularly at the Royal Saltworks at Arc-et-Senans in eastern France.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.