The D430 follows the Vosges mountain crest for 80 km from Cernay to Sainte-Marie-aux-Mines — wide views over the Rhine plain to the Black Forest in Germany, with winstub villages every 20 km for choucroute and Riesling. The WWI Hartmannswillerkopf battlefield runs directly alongside the road.
Clone it to your planner, customize dates and stops, then ride. All free.