Passy is a commune in the Haute-Savoie department in the Auvergne-Rhône-Alpes region in south-eastern France. It is part of the urban ar…Passy is a commune in the Haute-Savoie department in the Auvergne-Rhône-Alpes region in south-eastern France. It is part of the urban area of Sallanches. Located there is the Sancellemoz sanatorium, where Professor Marie Curie died in 1934.