Fortified Sector of Altkirch

Originally planned as a full extension of the Maginot Line with artillery ouvrages, the sector's fortifications were scaled back and chiefly took the form of casemates and blockhouses.

The region bordering Switzerland was treated as a low-priority area, but received a substantial number of casemates and blockhouses nonetheless.

[7] Three more resistance centers were proposed at Stetten, Ransbach-le-Haut and Trois-Maisons in 1937, but were replaced by more casemates, prepared for mobile 155mm and 240mm howitzers to cover the bridges at Basel and Huningue.

[10] The sector includes, in order from north to south, the following significant casemates and blockhouses in each sub-sector: 171st Fortress Infantry Regiment (171e Régiment d'Infanterie de Forteresse (RIF)), Lt.

Four heavy gun emplacements were planned:[7] Troop barracks were located at Uffheim, near Ranspach-le-Bas, near Bettlach, Ferrette and Raedersdorf.

[11] Additionally, 47 positions were planned by the Main d'Oeuvre Militaire (MOM)), which was in charge of small-scale fortifications, on the Glasenberg massif looking into Switzerland.

[7] The German offensive (Operation Kleiner Bär) across the Rhine was concentrated in the area near and to the north of Colmar, with little fighting in the Altkirch sector.

The second and third battalions were captured at Masevaux, while the remainder of the regiment, now amounting to about one hundred men, retreated through the Stiftkopf forest, ending up at the Tête-de-Neuf-Bois.