Fortified Sector of Mulhouse

The Fortified Sector of Mulhouse (Secteur Fortifié de Mulhouse) was the French military organization that in 1940 controlled the section of the French frontier with Germany in the vicinity of Mulhouse. The sector's principal defense was the Rhine itself, which could be crossed only by boat or by seizing a bridge crossing. The sector's fortifications chiefly took the form of casemates and blockhouses. The sector did not see significant action during the Battle of France, since the German crossings of the Rhine took place further north, near Colmar. The fortifications in the sector were built as part of the overall plan for the Maginot Line, but did not include the major fortified positions that characterized the Maginot Line of northeastern France. The sector did not see significant fighting in World War II. It was bordered to the north by the Fortified Sector of Colmar and on the south by the Fortified Sector of Altkirch.