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A belt of massive fortifications was established around the city, most of which still stands today, renamed after French generals and generally classified as Monuments historiques; most notably Fort Roon (now Fort Desaix) and Fort Podbielski (now Fort Ducrot) in Mundolsheim, Fort von Moltke (now Fort Rapp) in Reichstett, Fort Bismarck (now Fort Kléber) in Wolfisheim, Fort Kronprinz (now Fort Foch) in Niederhausbergen, Fort Kronprinz von Sachsen (now Fort Joffre) in Holtzheim and Fort Großherzog von Baden (now Fort Frère) in Oberhausbergen.

Where is for Kronprinz von Sachsen located?
Holtzheim