Day four starts at the edge of the Vosges and first drops downhill. From Osenbach, the route rolls through Soultzmatt and Rouffach, leaving the vineyard slopes for the Alsatian plain. The view opens, the roads become straighter, and the rhythm changes from small wine villages to fields, canals and flat connecting roads. Via the Dessenheim and Weckolsheim area, the route approaches Neuf-Brisach and Volgelsheim before reaching the Rhine near Breisach. On the German side, the day stays open and calm at first. The route crosses the villages west of Freiburg, with the Kaiserstuhl behind and the Black Forest ahead. Via Merdingen, Waltershofen and western Freiburg, it returns to the city.
