Ouvrage Four-à-Chaux is a ''gros ouvrage'' of the

Maginot Line The Maginot Line (; ), named after the Minister of War (France), French Minister of War André Maginot, is a line of concrete fortifications, obstacles and weapon installations built by French Third Republic, France in the 1930s to deter invas ...

, located in the community of

Lembach Lembach is a commune in the Bas-Rhin department and Grand Est region of north-eastern France. Etymology The toponym ''Lembach'' is of Germanic origin, cognate to modern German Lehm, denoting ''clay''. The Germanic hydronym '' *-bak(i)'' enter ...

, France, in the

Bas-Rhin département Bas-Rhin () is a department in Alsace which is a part of the Grand Est region of France. The name means 'Lower Rhine', referring to its lower altitude among the two French Rhine departments: it is downstream of the Haut-Rhin (Upper Rhine) depa ...

. Four à Chaux was adjoined by ''petit ouvrage''

and ''gros ouvrage'' Hochwald, and faced the German frontier as part of the Fortified Sector of the Vosges. A "four à chaux" is a

lime kiln A lime kiln is a kiln used for the calcination of limestone (calcium carbonate) to produce the form of lime called ''quicklime'' (calcium oxide). The chemical equation for this reaction is: CaCO3 + heat → CaO + CO2 This reaction can tak ...

in French, and the ''ouvrage'' was located in the area of a limestone quarry and kiln, which operated until 1939. Four-à-Chaux was bombarded by the invading Germans in late June 1940 during the

Battle of France The Battle of France (; 10 May – 25 June 1940), also known as the Western Campaign (), the French Campaign (, ) and the Fall of France, during the Second World War was the Nazi Germany, German invasion of the Low Countries (Belgium, Luxembour ...

with both aerial attacks and artillery bombardments. Four-à-Chaux survived to surrender at the end of the month. Block 1 was destroyed by the Germans before retreating in the face of American advances in 1945. During the 1950s Four-à-Chaux was renovated and reoccupied against a perceived threat from the

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

. It fell out of use in the 1970s, and is now operated as a museum.

Design and construction

The site was surveyed by CORF (''Commission d'Organisation des Régions Fortifiées''), the Maginot Line's design and construction agency; Lembach was approved for construction in July 1931. The ''gros ouvrage'' was intended to receive a second 75mm gun turret in a second phase of construction, never pursued.Mary, Tome 3, p. 133 Due to its compact arrangement, Four-à-Chaux did not receive an electrified internal rail system; the garrison pushed carts on the rails between the blocks. The fort also features an

artesian well An artesian well is a well that brings groundwater to the surface without pumping because it is under pressure within a body of rock or sediment known as an aquifer. When trapped water in an aquifer is surrounded by layers of Permeability (ea ...

.Kaufmann 2011, p. 246

Description

Four-à-Chaux is a position of medium importance on the Line, covering an area of 26 hectares, 4.5 km of subterranean galleries and six combat blocks. The ''ouvrage'' comprises eight blocks, with six combat blocks and two entries. The significant change in level between the combat blocks and the ammunition entrance required an inclined gallery immediately after the ammunition entrance. There is a 24-meter elevation difference between the ammunition entrance and the higher personnel entrance. In contrast to most ''gros ouvrages'' in northeastern France, Four-à-Chaux's internal railway system was not electrified. A drainage gallery was built to function as an emergency exit from the area of the ''caserne''. *Block 1: Artillery block with two automatic rifle cloches (GFM) and one 135mm retractable twin gun turret. The interior of the block was destroyed by the Germans during explosives effects testing. *Block 2: Artillery block with one GFM cloche, one twin machine gun cloche (JM) and one 75mm retractable twin gun turret. *Block 3: Artillery block with one GFM cloche, one grenade launcher cloche (LG) and one 81mm retractable twin mortar turret. *Block 4: Observation block with one GFM cloche, two JM cloches and one observation cloche (VDP). *Block 5: Infantry block with one GFM cloche and one retractable twin machine gun turret. *Block 6: Infantry block with one GFM cloche, one VDP cloche, one JM cloche, one twin machine gun embrasure and one machine gun (JM)/ 47mm anti-tank gun embrasure (JM/AC47). The block was extensively renovated in the 1950s. *Personnel entrance: one machine gun embrasure (JM) and one GFM cloche, as well as a false GFM cloche. *Ammunition entrance: one JM/AC 47 anti-tank gun embrasure and two GFM cloches.

Casemates and shelters

A detached

casemate A casemate is a fortified gun emplacement or armoured structure from which guns are fired, in a fortification, warship, or armoured fighting vehicle.Webster's New Collegiate Dictionary When referring to antiquity, the term "casemate wall" ...

is nearby: * Casemate de Schmelzbach Ouest: Single block with one JM/AC47 embrasure, one twin machine gun embrasure and a GFM cloche.

Manning

The 1940 manning of the ''ouvrage'' under the command of Commandant Exbrayat comprised 491 men and 19 officers of the 165th Fortress Infantry Regiment. The units were under the umbrella of the 5th Army. The nearby Casernement de Lembach provided peacetime above-ground barracks and support services to Four-à-Chaux and other positions in the area.

History

:''See Fortified Sector of the Vosges for a broader discussion of the Vosges sector of the Maginot Line.''

1940

On 19 June 1940, the German 215th Infantry Division attacked in the area immediately to the west of Lembach, between the river Schwartzbach and Lembach. Later in the day, Four-à-Chaux and other ''ouvrages'' were bombed by ''

Stuka The Junkers Ju 87, popularly known as the "Stuka", is a German dive bomber and ground-attack aircraft. Designed by Hermann Pohlmann, it first flew in 1935. The Ju 87 made its combat debut in 1937 with the Luftwaffe's Condor Legion during the ...

s'' with no significant effect. Four-à-Chaux's 135mm and 75mm gun turrets fired on the Germans throughout the day. The next day an attack was repelled with artillery support from Hochwald. Four-à-Chaux was heavily bombarded from the air and from German artillery during the period. The German advance continued into the Vosges region, but did not directly attack Four-à-Chaux with infantry. Four-à-Chaux formally surrendered on 1 July 1940.

1944–1945

Four-à-Chaux saw little action during the Lorraine Campaign, where most action took place around Hochwald and Schoenenbourg. Block 1 was destroyed using explosives by the Germans before the surrender in 1945.

Cold War

In the 1950s interest in the Maginot Line was renewed. In 1951, Lembach, Four-à-Chaux, Hochwald and Schoenenbourg were designated the ''Môle de Haguenau'', a point of resistance against a potential invasion by forces of the

Warsaw Pact The Warsaw Pact (WP), formally the Treaty of Friendship, Co-operation and Mutual Assistance (TFCMA), was a Collective security#Collective defense, collective defense treaty signed in Warsaw, Polish People's Republic, Poland, between the Sovi ...

. Four-à-Chaux was repaired and put in a state of readiness in 1951–52, with the exception of the destroyed Block 1.Mary, Tome 5, pp. 161–162 By the late 1950s interest in fixed fortifications was waning after France developed a nuclear deterrent. The money needed to maintain and upgrade the fortifications was diverted for the nuclear programs. Four-à-Chaux was not manned or maintained after the early 1970s.Mary, Tome 5, p. 173

Current condition

Today, Four-à-Chaux is open to the public under the guidance of the SILE ''(Syndicat d'Initiative de Lembach et Environs)'' association. The guided visit includes Block 2, the barracks, principal gallery, ''usine'' and the museum. The ''ouvrage'' may be visited throughout the year. The surface of the ''ouvrage'' is not accessible due to the presence of unexploded ordnance.

Notes

References

Bibliography

*Allcorn, William. ''The Maginot Line 1928–45.'' Oxford: Osprey Publishing, 2003. *Degon, André; Zylberyng, Didier, ''La Ligne Maginot: Guide des Forts à Visiter,'' Editions Ouest-France, 2014. *Kaufmann, J.E. and Kaufmann, H.W. ''Fortress France: The Maginot Line and French Defenses in World War II'', Stackpole Books, 2006. *Kaufmann, J.E., Kaufmann, H.W., Jancovič-Potočnik, A. and Lang, P. ''The Maginot Line: History and Guide'', Pen and Sword, 2011. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 1.'' Paris, Histoire & Collections, 2001. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 2.'' Paris, Histoire & Collections, 2003. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 3.'' Paris, Histoire & Collections, 2003. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 5.'' Paris, Histoire & Collections, 2009.