Fortified Sector of the Vosges

The Fortified Sector of the Vosges (Secteur Fortifiée des Vosges) was the French military organization that in 1940 controlled the section of the Maginot Line at the northern end of the Vosges Mountains in northeastern France. The sector was bordered to the west by the Fortified Sector of Rohrbach and to the east by the Fortified Sector of Haguenau. The sector featured two gros ouvrages mounting heavy artillery at either end of the sector and one petit ouvrage mounting infantry weapons, linked by a line of casemates. The sector was attacked in 1940 by German forces in the Battle of France. German forces penetrated the casemate line and moved behind French lines. Despite the withdrawal of the mobile forces that supported the fixed fortifications, the three ouvrages successfully fended off German assaults before the Second Armistice at Compiègne, but were unable to hinder German activities to their south. The positions and their garrisons finally surrendered on 1 July 1940. Following the war several positions were reactivated for use during the Cold War. One position, Ouvrage Four-à-Chaux, is open to the public and may be visited.

The Vosges sector was part of the larger Fortified Region of the Lauter, a strongly defended area between the Sarre to the west and the Rhine valley to the east. The Lauter region was more important during the planning and construction phase of the Maginot Line than it was in the operational phase of the Line, when the sectors assumed prominence. The Fortified Region of the Lauter was dissolved as a military organization on 5 March 1940, becoming the 43rd Fortress Army Corps.

The sector was anchored at either end by Grand-Hohékirkel on the west and Lembach-Four-à-Chaux on the east. In between the Line was filled in with casemates and blockhouses, with the stretch from Glasbronn to Windstein located behind the Swachwartzbach stream. This central portion of the depended on topography for much of its defense. The central casemate line was supported by the guns of the ouvrages and by the late addition of the casemates of Biesenberg and Windstein, which provided lateral covering fire with 75mm guns. Three proposed petit ouvrages were never constructed.

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