Ouvrage Bois-du-Four is a lesser work (petit ouvrage) in the Fortified Sector of the Crusnes of the Maginot Line. The ouvrage consists of a single large combat block without an underground gallery system, and is located between petit ouvrage Mauvais-Bois and gros ouvrage Bréhain, facing Luxembourg. A planned expansion, never carried out, was intended to enlarge Bois-du-Four into a fully equipped gros ouvrage. Bois-du-Four saw little action in either the Battle of France in 1940 or the Lorraine Campaign of 1944. It is preserved by the community of Villers-la-Montagne and may be visited.
Design and construction
Bois-du-Four was approved for construction in May 1932. It was completed at a cost of 9 million francs by the contractor Monod of Paris. It was designed as a unitary double casemate, occupying a prominent rise in a cleared area. In a second phase, Bois-du-Four was to be expanded to a plan that would result in a close resemblance to its neighbor Bréhain, with five additional blocks mounting artillery, as well as remote entrances for munitions and personnel, and an extensive network of deep underground galleries. The rise in tensions between France and Germany in the late 1930s prevented this second phase from being pursued.
Description
Only Block 1 of the proposed gros ouvrage was actually built, with five more combat blocks and two entry blocks deferred to a second phase that was never pursued. The large single block was arranged on two levels with a remarkably heavy armament. The proposed gros ouvrage would have been one of the most heavily armed artillery positions in the Line.
The single existing block was armed as follows: Block 1: combined infantry/artillery/entrance block with three automatic rifle cloches (GFM), one observation cloche (VDP) and one machine gun turret, as well as seven light machine guns, two heavy twin machine guns, three machine gun/47 mm anti-tank guns (JM/AC47), all in embrasures, and two 81mm mortars on the lower level. This block would have been the most northerly of the fully constructed ensemble.
The planned additional blocks were: Block 2 (unbuilt): Artillery block with one twin 75mm gun turret and one GFM cloche. Block 3 (unbuilt): Artillery block with one twin 75mm gun turret and one GFM cloche. Block 4 (unbuilt): Artillery block with one twin 75mm gun turret and one GFM cloche. Block 5 (unbuilt): Artillery block with one twin 135mm gun turret, one grenade launcher cloche (LG) and one GFM cloche. Block 6 (unbuilt): Artillery block with two GFM cloches, two machine gun cloches (JM), two AC47/JM embrasures and two light machine gun embrasures. Personnel entry (unbuilt): two GFM cloches, one grenade launcher cloche, two AC47/JM embrasures and two light machine gun embrasures. Munitions entry (unbuilt): two GFM cloches, one AC47/JM embrasure, one heavy twin machine gun and two light machine gun embrasures.
If built as intended, Bois-du-Four would have resembled its neighbor Bréhain, apart from Bois-du-Four's unusual initial block. A compact arrangement of combat blocks would have been connected to separate munitions and personnel entrances via a long, deeply buried underground gallery of more than in length, with a utility area, barracks and an "M1" magazine located near the entries. The entries were to be located in a small ravine, giving shelter and allowing for simpler access to the level of the galleries.
Casemates and shelters
A series of detached casemates and infantry shelters surround Bois-du-Four, including
Casemate de Villiers-la-Montagne Ouest: Single block with one JM/AC47 embrasure, one JM embrasure, one 81mm mortar cloche and one GFM cloche. Observatiore de Villiers-la-Montagne Centre: Single block with one JM/AC47 embrasure, one JM embrasure and one GFM cloche. Casemate de Villiers-la-Montagne Est: Single block with one JM/AC47 embrasure, one JM embrasure, one 81mm mortar cloche and one GFM cloche. Casemate de Verbusch Ouest: Single block with one JM/AC47 embrasure, one JM embrasure and two GFM cloches. Casemate de Verbusch Est: Single block with one JM/AC47 embrasure, one JM embrasure, one 81mm mortar cloche and one GFM cloche. Observatiore de la Ferme du Bois-du-Four: Observation block with one VP observation cloche and one GFM cloche, reporting to Bréhain. Casemate de la Ferme Thiéry: Single block with one JM/AC47 embrasure, one JM embrasure and two GFM cloches. Casemate de Bourène Ouest: Block with one mortar cloche and one GFM cloche. Casemate de Bourène Est: Double block with two JM/AC47 embrasure, two JM embrasure and two GFM cloches.