Milon-la-Chapelle is a commune in the Yvelines department in the Île-de-France region in north-central France. As of 2020, it is the commune …Milon-la-Chapelle is a commune in the Yvelines department in the Île-de-France region in north-central France. As of 2020, it is the commune with the third highest median per capita income in France. A chapel in the village, the Église de l'Assomption de la très Sainte Vierge, has a bas-relief sculpture by Georges Saupique.