Maginot line - wikipedia Maginot line Maginot Line Ligne Maginot Eastern France Entrance to Ouvrage Schoenenbourg, Maginot Line in Alsace Type Defensive line Site information Controlled by France Open to the public No Condition Mostly intact, through the preservation of the French Government Site history Built 1929 -- 1938 Built by Paul Painlevé, Colonel Tricaud Named after André Maginot ( French Minister of War, late 1920s - early 1930s ) In use 1935 -- 1969 Materials Concrete, steel, iron Battles / wars World War II Battle of France ( 1940 ) Operation Nordwind ( 1945 ) The Maginot Line ( French : Ligne Maginot, IPA : ( liɲ maʒino ) ), named after the French Minister of War André Maginot, was a line of concrete fortifications, obstacles, and weapon installations built by France in the 1930s to deter invasion by Germany and force them to move around the fortifications. Constructed on the French side of its borders with Italy, Switzerland, Germany, and Luxembourg, the line did not extend to the English Channel due to French strategy that envisioned a move into Belgium to counter a German assault. Based on France 's experience with trench warfare during World War I, the massive Maginot Line was built in the run - up to World War II, after the Locarno Conference gave rise to a fanciful and optimistic `` Locarno spirit ''. French military experts extolled the Line as a work of genius that would deter German aggression, because it would slow an invasion force long enough for French forces to mobilize and counterattack. The Maginot Line was impervious to most forms of attack, including aerial bombings and tank fire, and had underground railways as a backup ; it also had state - of - the - art living conditions for garrisoned troops, supplying air conditioning and eating areas for their comfort. Instead of attacking directly, the Germans invaded through the Low Countries, bypassing the Line to the north. French and British officers had anticipated this : when Germany invaded the Netherlands and Belgium, they carried out plans to form an aggressive front that cut across Belgium and connected to the Maginot Line. However, the French line was weak near the Ardennes forest. The French believed this region, with its rough terrain, would be an unlikely invasion route of German forces ; if it was traversed, it would be done at a slow rate that would allow the French time to bring up reserves and counterattack. The German Army, having reformulated their plans from a repeat of the First World War - era plan, became aware of and exploited this weak point in the French defensive front. A rapid advance through the forest and across the River Meuse encircled much of the Allied forces, resulting in a sizeable force being evacuated at Dunkirk leaving the forces to the south unable to mount an effective resistance to the German invasion of France. The line has since become a metaphor for expensive efforts that offer a false sense of security. Contents 1 Purposes 2 Planning and construction 2.1 1927 : Allied Control Commission abolished 2.2 German economic superiority 2.3 War of long duration 3 Manning 4 Organization 5 Inventory 5.1 Ouvrages 5.2 Armoured cloches 5.3 Retractable turrets 5.4 Artillery 5.5 Anti-tank guns 6 Features 6.1 Czechoslovak connection 7 German invasion in World War II 8 After World War II 9 Post-war assessment 10 See also 11 Notes 12 References 13 Further reading 14 External links Purposes The Maginot Line was built to fulfil several purposes : To prevent a surprise German attack To deter a cross-border assault. To protect Alsace and Lorraine ( returned to France in 1918 ) and their industrial basin To save manpower ( France counted 39 million inhabitants, Germany 70 million ) To cover the mobilisation of the French Army ( which took between two and three weeks ) To push Germany into an effort to circumvent via Switzerland or Belgium, and allow France to fight the next war off of French soil to avoid a repeat of 1914 -- 1918. To be used as a basis for a counter-offensive Planning and construction The Maginot Line The defences were first proposed by Marshal Joffre. He was opposed by modernists such as Paul Reynaud and Charles de Gaulle, who favoured investment in armour and aircraft. Joffre had support from Marshal Henri Philippe Pétain, and there were a number of reports and commissions organised by the government. It was André Maginot who finally convinced the government to invest in the scheme. Maginot was another veteran of World War I ; he became the French Minister of Veteran Affairs and then Minister of War ( 1928 -- 1932 ). In January 1923, after Germany defaulted on reparations, the French Premier Raymond Poincaré responded by sending French troops to occupy Germany 's Ruhr region. During the ensuing Ruhrkampf ( `` Ruhr struggle '' ) between the Germans and the French that lasted until September 1923, Britain condemned the French occupation of the Ruhr, and a period of sustained Francophobia broke out in Britain, with Poincaré being vilified in Britain as a cruel bully punishing Germany with unreasonable reparations demands. The British -- who openly championed the German position on reparations -- applied intense economic pressure on France to change its policies towards Germany. At a conference in London in 1924 to settle the Franco - German crisis caused by the Ruhrkampf, the British Prime Minister Ramsay MacDonald successfully pressed the French Premier Édouard Herriot to make concessions to Germany. The British diplomat Sir Eric Phipps who attended the conference commented afterwards that : The London Conference was for the French ' man in the street ' one long Calvary as he saw M. Herriot abandoning one by one the cherished possessions of French preponderance on the Reparations Commission, the right of sanctions in the event of German default, the economic occupation of the Ruhr, the French - Belgian railroad Régie, and finally, the military occupation of the Ruhr within a year. The great conclusion that was drawn in Paris after the Ruhrkampf and the 1924 London conference was that France could not make unilateral military moves to uphold Versailles as the resulting British hostility to such moves was too dangerous to the republic. Beyond that, the French were well aware of the contribution of Britain and its Dominions to the victory of 1918, and French decision - makers believed that they needed Britain 's help to win another war ; the French could only go so far with alienating the British. From 1871 onwards, French elites had concluded that France had no hope of defeating Germany on its own, and France would need an alliance with another great power to defeat the Reich. 1927 : Allied Control Commission abolished In 1926, The Manchester Guardian ran an expose showing the Reichswehr had been developing military technology forbidden by the Treaty of Versailles in the Soviet Union, and the secret German - Soviet co-operation had started in 1921. The German statement following The Manchester Guardian 's article that Germany did not feel bound by the terms of Versailles and would violate them as much as possible gave much offense in France. Nonetheless, in 1927, the Allied Control Commission, which was responsible for ensuring that Germany complied with Part V of the Treaty of Versailles, was abolished as a goodwill gesture reflecting the `` Spirit of Locarno ''. When the Control Commission was dissolved, the commissioners in their final report issued a blistering statement, stating that Germany had never sought to abide by Part V and the Reichswehr had been engaging in covert rearmament all through the 1920s. Under the Treaty of Versailles France was to occupy the Rhineland region of Germany until 1935, but in fact the last French troops left the Rhineland in June 1930 in exchange for Germany accepting the Young Plan. As long as the Rhineland was occupied by the French, the Rhineland served as a type of collateral under which the French would annex the Rhineland in the event of Germany breaching any of the articles of the treaty, such as rearming in violation of Part V ; this threat was powerful enough to deter successive German governments all through the 1920s from attempting any overt violation of Part V. French plans as developed by Marshal Ferdinand Foch in 1919 were based on the assumption that in the event of a war with the Reich, the French forces in the Rhineland were to embark upon an offensive to seize the Ruhr. A variant of the Foch plan had been used by Poincaré in 1923 when he ordered the French occupation of the Ruhr. French plans for an offensive in the 1920s were realistic, as Versailles had forbidden Germany conscription, and the Reichswehr was limited to 100,000 men. Once the French forces left the Rhineland in 1930, this form of leverage with the Rhineland as collateral was no longer available to Paris, which from then on had to depend on Berlin 's word that it would continue to abide by the terms of the Versailles and Locarno treaties, which stated that the Rhineland was to stay demilitarized forever. Given that Germany had engaged in covert rearmament with the co-operation of the Soviet Union starting in 1921 ( a fact that had become public knowledge in 1926 ) and that every German government had gone out of its way to insist on the moral invalidity of Versailles, claiming it was based upon the so - called Kriegsschuldlüge ( `` War guilt lie '' ) that Germany started the war in 1914, the French had little faith that the Germans would willingly allow the Rhineland 's demilitarized status to continue forever, and believed that at some time in the future Germany would rearm in violation of Versailles, reintroduce conscription and remilitarize the Rhineland. The decision to build the Maginot Line in 1929 was a tacit French admission that without the Rhineland as collateral Germany was soon going to rearm, and that the terms of Part V had a limited lifespan. German economic superiority After 1918, the German economy was three times as large as that of France ; Germany had a population of 70 million compared to France 's 40 million and the French economy was hobbled by the need to reconstruct the enormous damage of World War I, while German territory had seen little fighting. French military chiefs were dubious about their ability to win another war against Germany on its own, especially an offensive war. French decision - makers knew that the victory of 1918 had been achieved because the British Empire and the United States were allies in the war and that the French would have been defeated on their own. With the United States isolationist and Britain stoutly refusing to make the `` continental commitment '' to defend France on the same scale as in World War I, the prospects of Anglo - American assistance in another war with Germany appeared to be doubtful at best. Versailles did not call for military sanctions in the event of Germany remilitarizing the Rhineland or breaking Part V ; while Locarno committed Britain and Italy to come to French aid in the event of a `` flagrant violation '' of the Rhineland 's demilitarized status, without defining what a `` flagrant violation '' would be. The British and Italian governments refused in subsequent diplomatic talks to define `` flagrant violation '', which led the French to place little hope in Anglo - Italian help if Germany should remilitarize the Rhineland. Given the diplomatic situation in the late 1920s, the Quai d'Orsay informed the government that French military planning should be based on a worst - case scenario that France would fight the next war against Germany without the help of Britain or the United States. France had an alliance with Belgium and with the states of the Cordon sanitaire, as the French alliance system in Eastern Europe was known. Although the alliances with Belgium, Poland, Czechoslovakia, Romania and Yugoslavia were appreciated in Paris, it was widely understood that this was no compensation for the absence of Britain and the United States. The French military was especially insistent that the population disparity made an offensive war of maneuver and swift advances suicidal as there would always be far more German divisions ; a defensive strategy was needed to counter Germany. The French assumption was always that Germany would not go to war without conscription, which would allow the German Army to take advantage of the Reich 's numerical superiority. Without the natural defensive barrier provided by the Rhine river, French generals argued that France needed a new defensive barrier made of concrete and steel to replace it. The power of properly dug - in defensive trenches had been amply demonstrated during World War I, when a few soldiers manning a single machine gun post could kill hundreds of the enemy in the open and therefore building a massive defensive line with subterranean concrete shelters was the most rational use of French manpower. The American historian William Keylor wrote that given the diplomatic conditions of 1929 and likely trends - with the United States isolationist and Britain unwilling to make the `` continental commitment '' - the decision to build the Maginot Line was not irrational and stupid, as building the Maginot Line was a sensible response to the problems that would be created by the coming French withdrawal from the Rhineland in 1930. Part of the rationale for the Maginot Line stemmed from the severe French losses during the First World War, and their effect on the French population. The drop in the birth rate during and after the war, resulting in a national shortage of young men, created an `` echo '' effect in the generation that provided the French conscript army in the mid-1930s. Faced with a manpower shortage, French planners had to rely more on older and less fit reservists, who would take longer to mobilize and would diminish French industry because they would leave their jobs. Static defensive positions were therefore intended not only to buy time but to economise on men by defending an area with fewer and less mobile forces. In 1940, France deployed about twice as many men, 36 divisions ( roughly one third of its force ), for the defence of the Maginot Line in Alsace and Lorraine, whereas the opposing German Army Group C only contained 19 divisions, fewer than a seventh of the force committed in the Manstein Plan for the invasion of France. Reflecting memories of World War I, the French General Staff had developed the concept of la puissance du feu ( `` the power of fire '' ), the power of artillery dug in and sheltered by concrete and steel, to inflict devastating losses on an attacking force. War of long duration Map of the principal fortified section of the Maginot Line French planning for war with Germany was always based on the assumption that the war would be la guerre de longue durée ( the war of the long duration ), in which the superior economic resources of the Allies would gradually grind the Germans down. The fact that the Wehrmacht embraced the strategy of Blitzkrieg ( Lightning War ) with the vision of swift wars in which Germany would win quickly via a knock - out blow, was a testament to the fundamental soundness of the concept of la guerre de longue durée. Germany had the largest economy in Europe but lacked many of the raw materials necessary for a modern industrial economy ( making the Reich vulnerable to a blockade ) and the ability to feed its population. The guerre de longue durée strategy called for the French to halt the expected German offensive meant to give the Reich a swift victory ; afterwards, there would be an attrition struggle ; once the Germans were exhausted France would begin an offensive to win the war. The Maginot Line was intended to block the main German blow if it should come in eastern France and to divert the main blow through Belgium, where French forces would meet and stop the Germans. The Germans were expected to fight costly offensives, whose failures would sap the strength of the Reich, while the French waged a total war with the resources of France, its empire and allies mobilized for the war. Besides the demographic reasons, a defensive strategy served the needs of French diplomacy towards Great Britain. The French imported a third of their coal from Britain and 32 percent of all imports through French ports were carried by British ships. Of French trade, 35 percent was with the British Empire and the majority of the tin, rubber, jute, wool and manganese used by France came from the British Empire. About 55 percent of overseas imports arrived in France via the Channel ports of Calais, Le Havre, Cherbourg, Boulogne, Dieppe, Saint - Malo and Dunkirk. Germany had to import most of its iron, rubber, oil, bauxite, copper and nickel, making naval blockade a devastating weapon against the German economy. For economic reasons, the success of the strategy of la guerre de longue durée would at very least require Britain to maintain a benevolent neutrality, preferably to enter the war as an ally as British sea power could protect French imports while depriving Germany of hers. A defensive strategy based on the Maginot Line was an excellent way of demonstrating to Britain that France was not an aggressive power and would only go to war in the event of German aggression, a situation that would make it more likely that Britain would enter the war on France 's side. The line was built in several phases from 1930 by the Service Technique du Génie ( STG ) overseen by Commission d'Organisation des Régions Fortifiées ( CORF ). The main construction was largely completed by 1939, at a cost of around 3 billion French francs. The line stretched from Switzerland to Luxembourg and a much lighter extension was extended to the Strait of Dover after 1934. The original construction did not cover the area chosen by the Germans for their first challenge, which was through the Ardennes in 1940, a plan known as Fall Gelb ( Case Yellow ), due to the neutrality of Belgium. The location of this attack, because of the Maginot Line, was through the Belgian Ardennes forest ( sector 4 ), which is off the map to the left of Maginot Line sector 6 ( as marked ). Manning Maginot Line fortifications were manned by specialist units of fortress infantry, artillery and engineers. The infantry manned the lighter weapons of the fortresses, and formed units with the mission of operating outside if necessary. Artillery troops operated the heavy guns and the engineers were responsible for maintaining and operating other specialist equipment, including all communications systems. All these troops wore distinctive uniform insignia and considered themselves among the elite of the French Army. During peacetime, fortresses were only partly manned by full - time troops. They would be supplemented by reservists who lived in the local area, and who could be quickly mobilised in an emergency. Full - time Maginot Line troops were accommodated in barracks built close by the fortresses. They were also accommodated in complexes of wooden housing adjacent to each fortresses, which were more comfortable than living inside, but which were not expected to survive wartime bombardment. Training was carried out at a fortress near the town of Bitche, built in a military training area and so capable of live fire exercises. This was impossible elsewhere as the other parts of the line were located in civilian areas. Organization Block 14 at Ouvrage Hochwald in 1940 Side view diagram of the operation of a retractable turret : 75 mm gun of block 3 in Ouvrage Schoenenbourg Casemate of Dambach Nord, Fortified Sector of the Vosges, Sub-sector of Philippsbourg Layout of Ouvrage Hackenberg, one of the largest fortress complexes Although the name `` Maginot Line '' suggests a rather thin linear fortification, it was quite deep, varying ( from the German border to the rear area ) from 20 -- 25 kilometres ( 12 -- 16 miles ). It was composed of an intricate system of strong points, fortifications and military facilities such as border guard posts, communications centres, infantry shelters, barricades, artillery, machine gun and anti-tank gun emplacements, supply depots, infrastructure facilities and observation posts. These various structures reinforced a principal line of resistance made up of the most heavily armed ouvrages, which can be roughly translated as fortresses or big defensive works. From front to rear, ( east to west ) the line was composed of : 1. Border Post line : This consisted of blockhouses and strong houses, which were often camouflaged as inoffensive residential homes, built within a few metres of the border and manned by troops so as to give the alarm in the event of a surprise attack and to delay enemy tanks with prepared explosives and barricades. 2. Outpost and Support Point line : Approximately 5 km ( 3 mi ) behind the border, a line of anti-tank blockhouses that were intended to provide resistance to armoured assault, sufficient to delay the enemy so as to allow the crews of the C.O.R.F. ouvrages to be ready at their battle stations. These outposts covered the main passages within the principal line. 3. Principal line of resistance : This line began 10 km ( 6 mi ) behind the border. It was preceded by anti-tank obstacles made of metal rails planted vertically in six rows, with heights varying from 0.70 -- 1.40 metres ( 2 ft 4 in -- 4 ft 7 in ) and buried to a depth of 2 m ( 6 ft 7 in ). These anti-tank obstacles extended from end to end in front of the main works, over hundreds of kilometers, interrupted only by extremely dense forests, rivers, or other nearly impassable terrain. The anti-tank obstacle system was followed by an anti-personnel obstacle system made primarily of dense barbed wire. Anti-tank road barriers also made it possible to block roads at necessary points of passage through the tank obstacles. 4. Infantry Casemates : These bunkers were armed with twin machine - guns ( abbreviated as JM -- Jumelage de mitrailleuses -- in French ) and anti-tank guns of 37 or 47 mm ( 1.5 or 1.9 in ). They could be single ( with a firing room in one direction ) or double ( two firing rooms, in opposite directions ). These generally had two floors, with a firing level and a support / infrastructure level that provided the troops with rest and services ( power generating units, reserves of water, fuel, food, ventilation equipment, etc. ). The infantry casemates often had one or two `` cloches '' or turrets located on top of them. These GFM cloches were sometimes used to emplace machine guns or observation periscopes. They were manned by 20 to 30 men. 5. Petits ouvrages : These small fortresses reinforced the line of infantry bunkers. The petits ouvrages were generally made up of several infantry bunkers, connected by a tunnel network with attached underground facilities, such as barracks, electric generators, ventilation systems, mess halls, infirmaries and supply caches. Their crew consisted of between 100 and 200 men. 6. Gros Ouvrages : These fortresses were the most important fortifications on the Maginot Line, having the sturdiest construction and the heaviest artillery. These were composed of at least six `` forward bunker systems '' or `` combat blocks '', as well as two entrances, and were connected via a network of tunnels that often featured narrow gauge electric railways for transport between bunker systems. The blocks contained infrastructure such as power stations, independent ventilating systems, barracks and mess halls, kitchens, water storage and distribution systems, hoists, ammunition stores, workshops and stores of spare parts and food. Their crews ranged from 500 to more than 1,000 men. Blockhouse MOM ( Main d'Oeuvre Militaire ) de Richtolsheim -- Secteur Fortifié de Colmar -- Sous secteur de Hilsenheim 7. Observation Posts were located on hills that provided a good view of the surrounding area. Their purpose was to locate the enemy and direct and correct the indirect fire of artillery as well as to report on the progress and position of key enemy units. These are large reinforced buried concrete bunkers, equipped with armoured turrets containing high - precision optics, connected with the other fortifications by field telephone and wireless transmitters ( known in French by the acronym T.S.F., Télégraphie Sans Fils ). 8. Telephone Network : This system connected every fortification in the Maginot Line, including bunkers, infantry and artillery fortresses, observation posts and shelters. Two telephone wires were placed parallel to the line of fortifications, providing redundancy in the event of a wire getting cut. There were places along the cable where dismounted soldiers could connect to the network. 9. Infantry Reserve Shelters : These were found from 500 -- 1,000 m ( 1,600 -- 3,300 ft ) behind the principal line of resistance. These were buried concrete bunkers designed to house and shelter up to a company of infantry ( 200 to 250 men ) and had such features as electric generators, ventilation systems, water supplies, kitchens and heating, which allowed their occupants to hold out in the event of an attack. They could also be used as a local headquarters and as a base for counter-attacks. Anti-tank rails around casemate 9 of the Hochwald ditch 10. Flood Zones were natural basins or rivers that could be flooded on demand and thus constitute an additional obstacle in the event of an enemy offensive. 11. Safety Quarters were built near the major fortifications so fortress ( ouvrage ) crews could reach their battle stations in the shortest possible time in the event of a surprise attack during peacetime. 12. Supply depots. 13. Ammunition dumps. 14. Narrow Gauge Railway System : A network of 600 mm ( 1 ft 11 ⁄ in ) narrow gauge railways was built so as to rearm and resupply the main fortresses ( ouvrages ) from supply depots up to 50 km ( 31 mi ) away. Petrol - engined armoured locomotives pulled supply trains along these narrow - gauge lines. ( A similar system was developed with armoured steam engines back in 1914 -- 1918. ) 15. High - voltage Transmission Lines, initially above - ground but then buried, and connected to the civil power grid, provided electric power to the many fortifications and fortresses. 16. Heavy rail artillery was hauled in by locomotives to planned locations to support the emplaced artillery located in the fortresses, which was intentionally limited in range to 10 -- 12 km ( 6 -- 7 mi ). Inventory Ouvrages There are 142 ouvrages, 352 casemates, 78 shelters, 17 observatories and around 5,000 blockhouses in the Maginot Line. Armoured cloches There are several kinds of armoured cloches. The word cloche is a French term meaning bell due to its shape. All cloches were made in an alloy steel. Cloches are non-retractable turrets. The most widespread are the GFM cloches, where GFM means Guetteur fusil - mitrailleur ( machine - gun sentry ). They are composed of three to four openings, called crenels or embrasures. These crenels may be equipped as follows : Rifle machine - gun, direct vision block, binoculars block or 50 mm ( 2.0 in ) mortar. Sometimes, the cloche is topped by a periscope. There are 1,118 GFM cloches on the line. Almost every block, casemate and shelter is topped by one or two GFM cloches. The JM cloches ( jumelage de mitrailleuses or `` twin machine - guns '' ) are the same as the GFM cloches except that they have one opening equipped with a pair of machine - guns. There are 174 JM cloches on the line. There are 72 AM cloches ( armes mixtes or `` mixed weapons '' ) on the line, equipped with a pair of machine guns and a 25 mm ( 1.0 in ) anti-tank gun. Some GFM cloches were transformed into AM cloches in 1934. ( The aforementioned total does not include these modified cloches. ) There are 75 LG cloches ( lance - grenade or `` grenade launcher '' ) on the line. Those cloches are almost completely covered by concrete, with only a small hole to launch grenades through for local defence. There are 20 VP cloches ( vision périscopique or `` periscopic vision '' ) on the line. These cloches could be equipped with several different periscopes. Like the LG cloches, they were almost completely covered by concrete. The VDP cloches ( vision directe et périscopique or `` direct and periscopic vision '' ) are similar to the VP cloches, but have two or three openings to provide a direct view. Consequently, they were not covered by concrete. GFM cloche JM cloche AM cloche LG cloche VP cloche VDP cloche Retractable turrets The line included the following retractable turrets. 21 turrets of 75 mm ( 3.0 in ) model 1933 12 turrets of 75 mm ( 3.0 in ) model 1932 1 turret of 75 mm ( 3.0 in ) model 1905 17 turrets of 135 mm ( 5.3 in ) 21 turrets of 81 mm ( 3.2 in ) 12 turrets for mixed weapons ( AM ) 7 turrets for mixed weapons + mortar of 50 mm ( 2.0 in ) 61 turrets of machine - guns 75 mm ( 3.0 in ) Turret model 1932 135 mm ( 5.3 in ) Turret 81 mm ( 3.2 in ) Turret Machine - gun Turret AM ( Mixed - Weapons ) Turret Artillery Both static and mobile artillery units were assigned to defend the Maginot Line. Régiments d ' artillerie de position ( RAP ) consisted of static artillery units. Régiments d ' artillerie mobile de forteresse ( RAMF ) consisted of mobile artillery. Anti-tank guns Canon de 25mm SA Mle1934 SA - L Mle1937 ( Puteaux ) L / 72 Features 81 mm ( 3.2 in ) mortar The specification of the defenses was very high, with extensive and interconnected bunker complexes for thousands of men ; there were 45 main forts ( grands ouvrages ) at intervals of 15 km ( 9.3 mi ), 97 smaller forts ( petits ouvrages ) and 352 casemates between, with over 100 km ( 62 mi ) of tunnels. Artillery was coordinated with protective measures to ensure that one fort could support the next in line by bombarding it directly without harm. The largest guns were therefore 135 mm ( 5.3 in ) fortress guns ; larger weapons were to be part of the mobile forces and were to be deployed behind the lines. The fortifications did not extend through the Ardennes Forest ( which was believed to be impenetrable by Commander - in - Chief Maurice Gamelin ) or along France 's border with Belgium, because the two countries had signed an alliance in 1920, by which the French army would operate in Belgium if the German forces invaded. However, after France had failed to counter Germany 's remilitarisation of the Rhineland, Belgium -- thinking that France was not a reliable ally -- abrogated the treaty in 1936 and declared neutrality. France quickly extended the Maginot Line along the Franco - Belgian border, but not to the standard of the rest of the line. As the water table in this region is high, there was the danger of underground passages getting flooded, which the designers of the line knew would be difficult and expensive to overcome. In 1939 US Army officer Kenneth Nichols visited the Metz sector, where he was impressed by the formidable formations which he thought the Germans would have to outflank by driving through Belgium. In discussion with General Brousseau the commander of the Metz sector and other officers, the general outlined the French problem in extending the line to the sea in that placing the line along the Belgian - German border required the agreement of Belgium, but putting the line along the French - Belgian border relinquished Belgium to the Germans. Another complication was Holland, and the various governments never resolved their problems. Corridor inside the Fort Saint - Gobain near Modane in the Alps. The Decauville When the British Expeditionary Force landed in France in September 1939, they and the French reinforced and extended the Maginot line to the sea in a flurry of construction from 1939 -- 1940 accompanied by general improvements all along the line. The final line was strongest around the industrial regions of Metz, Lauter and Alsace, while other areas were in comparison only weakly guarded. In contrast, the propaganda about the line made it appear far greater a construction than it was ; illustrations showed multiple stories of interwoven passages and even underground railyards and cinemas. This reassured Allied civilians. Czechoslovak connection Czechoslovakia was also in fear of Hitler and began building its own defenses. As an ally of France, they were able to get advice on the Maginot design and apply it to Czechoslovak border fortifications. The design of the casemates is similar to the ones found in the southern part of the Maginot Line and photographs of them are often confused with Maginot forts. Following the Munich Agreement and the German occupation of Czechoslovakia, the Germans were able to use the Czech fortifications to plan attacks that proved successful against the western fortifications ( the Belgian Fort Eben - Emael is the best known example ). German invasion in World war II Battle of France Battle of France Royal Marine Ardennes Sedan Montcornet Saumur Maginot Line Weygand Plan Montcornet Arras Boulogne Calais Dunkirk Wormhoudt Dynamo Abbeville Lille Paula Alps Fall Rot Cycle Ariel Fall Braun Battle of the Netherlands Maastricht The Hague Rotterdam Zeeland The Grebbeberg Afsluitdijk Rotterdam Blitz Battle of Belgium Fort Eben - Emael KW Line Dyle Plan Hannut Gembloux Canal Lys Invasion of Luxembourg Schuster Line Combat block 1 at the fortress Limeiln ( ouvrage Four - à - Chaux, Alsace ), showing signs of German testing of explosives inside some fortresses between 1942 and 1944 The World War II German invasion plan of 1940 ( Sichelschnitt ) was designed to deal with the line. A decoy force sat opposite the line while a second Army Group cut through the Low Countries of Belgium and the Netherlands, as well as through the Ardennes Forest, which lay north of the main French defences. Thus the Germans were able to avoid a direct assault on the Maginot Line by violating the neutrality of Belgium, Luxembourg and the Netherlands. Attacking on 10 May, German forces were well into France within five days and they continued to advance until 24 May, when they stopped near Dunkirk. During the advance to the English Channel, the Germans overran France 's border defence with Belgium and several Maginot Forts in the Maubeuge area, whilst the Luftwaffe simply flew over it. On 19 May, the German 16th Army successfully captured the isolated petit ouvrage La Ferté ( southeast of Sedan ) after conducting a deliberate assault by combat engineers backed up by heavy artillery. The entire French crew of 107 soldiers was killed during the action. On 14 June 1940, the day Paris fell, the German 1st Army went over to the offensive in `` Operation Tiger '' and attacked the Maginot Line between St. Avold and Saarbrücken. The Germans then broke through the fortification line as defending French forces retreated southward. In the following days, infantry divisions of the 1st Army attacked fortifications on each side of the penetration ; successfully capturing four petits ouvrages. The 1st Army also conducted two attacks against the Maginot Line further to the east in northern Alsace. One attack successfully broke through a weak section of the line in the Vosges Mountains, but a second attack was stopped by the French defenders near Wissembourg. On 15 June, infantry divisions of the German 7th Army attacked across the Rhine River in Operation `` Small Bear '', penetrating the defences deep and capturing the cities of Colmar and Strasbourg. By early June the German forces had cut off the line from the rest of France and the French government was making overtures for an armistice, which was signed on 22 June in Compiègne. As the line was surrounded, the German Army attacked a few ouvrages from the rear, but were unsuccessful in capturing any significant fortifications. The main fortifications of the line were still mostly intact, a number of commanders were prepared to hold out, and the Italian advance had been successfully contained. Nevertheless, Maxime Weygand signed the surrender instrument and the army was ordered out of their fortifications, to be taken to POW camps. When the Allied forces invaded in June 1944, the line, now held by German defenders, was again largely bypassed ; fighting touched only portions of the fortifications near Metz and in northern Alsace towards the end of 1944. During the German offensive Operation Nordwind in January 1945, Maginot Line casemates and fortifications were utilized by Allied forces, especially in the region of Hatten - Rittershoffen, and some German units had been supplemented with flamethrower tanks in anticipation of this possibility. Stephen Ambrose wrote that in January 1945 `` a part of the line was used for the purpose it had been designed for and showed what a superb fortification it was. '' Here the Line ran east - west, around the villages of Rittershoffen and Hatten, south of Wissembourg. After World war II The view from a battery at Ouvrage Schoenenbourg in Alsace. A retractable turret is in the left foreground. After the war the line was re-manned by the French and underwent some modifications. With the rise of the French independent nuclear weapons by 1960 the line became an expensive anachronism. Some of the larger ouvrages were converted to command centres. When France withdrew from NATO 's military component ( in 1966 ) much of the line was abandoned, with the NATO facilities turned back over to French forces and the rest of it auctioned - off to the public or left to decay. A number of old fortifications have now been turned into wine cellars, a mushroom farm and even a disco. Besides that, a few private houses are built atop some of the blockhouses. The view of the village of Lembach in Alsace ( north - east ), taken from the combat unit number 5 of the fortress ouvrage Four - à - Chaux Ouvrage Rochonvillers was retained by the French Army as a command centre into the 1990s, but was deactivated following the disappearance of the Soviet threat. Ouvrage Hochwald is the only facility in the main line that remains in active service, as a hardened command facility for the French Air Force known as Drachenbronn Air Base. In 1968 when scouting locations for On Her Majesty 's Secret Service, producer Harry Saltzman used his French contacts to gain permission to use portions of the Maginot Line as SPECTRE headquarters in the film. Saltzman provided art director Syd Cain with a tour of the complex, but Cain said that not only would the location be difficult to light and film inside, but that artificial sets could be constructed at the studios for a fraction of the cost. The idea was shelved. Post-war assessment In analyzing the Maginot Line, Ariel Ilan Roth summarized its main purpose : it was not `` as popular myth would later have it, to make France invulnerable '', rather it was constructed `` to make the appeal of flanking ( the fortifications ) far outweigh the appeal of attacking them head on. '' J.E. Kaufmann and H.W. Kaufmann added to this, that prior to construction in October 1927, the Superior Council of War adopted the final design for the line and identified that one of the main missions would be to deter a German cross-border assault with only minimal force thus allowing `` the army time to mobilize. '' In addition, the French envisioned that the Germans would conduct a repeat of their First World War battleplan in order to flank the defences and drew up their overall strategy with that in mind. Julian Jackson highlighted one of the line 's roles was to facilitate this strategy by `` free ( ing ) manpower for offensive operations elsewhere... and to protect the forces of manoeuvre '' ; the latter included a more mechanized and modernized military, which would advance into Belgium and engage the German main thrust flanking the line. In support, Roth commented that French strategy envisioned one of two possibilities by advancing into Belgium : `` either there would be a decisive battle in which France might win, or, more likely, a front would develop and stabilize ''. The latter meant the next war 's destructive consequences would not take place on French soil. Post-war assessment of whether the Maginot Line served its purpose has been mixed. Due to its enormous cost, and its failure to prevent German forces from invading France, journalists and political commentators remain divided on whether the line was worthwhile. Historian Clayton Donnell commented `` If one believes the Maginot Line was built for the primary purpose of stopping a German invasion of France, most will consider it a massive failure and a waste of money... in reality, the line was not built to be the ultimate savior of France ''. Donnell argued that the primary purpose of `` prevent ( ing ) a concerted attack on France through the traditional invasion routes and to permit time for the mobilization of troops... was fulfilled '' as was the French strategy of forcing the Germans to enter Belgium, which ideally would have allowed `` the French to fight on favorable terrain ''. However, he noted that the French failed to use the line as the basis for an offensive. Marc Romanych and Martin Rupp highlight that `` poor decisions and missed opportunities '' plagued the line, and point to its purpose of conserving manpower : `` about 20 per cent of ( France 's ) field divisions remained inactive along the Maginot Line '', while Belgium was overrun and British and French forces evacuated at Dunkirk. They argue had these troops been moved north `` it is possible that Heeresgruppe A 's advance could have been blunted, giving time for Groupe d'armees 1 to reorganize ''. Kaufmann and Kaufmann commented `` When all is said and done, the Maginot Line did not fail to accomplish its original mission... it provided a shield that bought time for the army to mobilize... ( and ) concentrate its best troops along the Belgian border to engage the enemy. '' The psychological factor of the Maginot Line has also been discussed. Its construction created a false sense of security, which was widely believed by the French population. Kaufmann and Kaufmann comment that this was an unintended consequence of André Maginot 's efforts to `` focus the public 's attention on the work being done, emphasizing the role and nature of the line ''. This resulted in `` the media exaggerat ( ing ) his descriptions, turning the line into an impregnable fortified position that would seal the frontier ''. This false sense of security contributed `` to the development of the `` Maginot mentality '' ``. Jackson commented that `` it has often been alleged that the Maginot Line contributed to France 's defeat by making the military too complacent and defence - minded. Such accusations are unfounded. '' Historians have pointed to numerous reasons for the French defeat : faulty strategy and doctrine, dispersion of forces, the loss of command and control, poor communications, faulty intelligence that provided exaggerated German numbers, the slow nature of the French response to the German penetration of the Ardennes, and a failure to understand the nature and speed of the German doctrine. More seriously, historians have noted rather than the Germans doing what the French had envisioned, the French played into the Germans hand culminating in their defeat. When the French Army failed in Belgium, the Maginot Line covered their retreat. Romanych and Rupp indicate that, with the exception of the loss of several insignificant fortifications due to insufficient defending troops, the actual fortifications and troops `` withstood the test of battle '', repulsed numerous attacks, and `` withstood intense aerial and artillery bombardment. '' Kaufmann and Kaufmann point to the Maginot Line along the Italian border, which `` demonstrated the effectiveness of the fortifications... when properly employed. '' See also World War II portal Atlantic Wall Czechoslovak border fortifications List of Alpine Line ouvrages ( works ) List of Maginot Line ouvrages ( works ) Metaxas Line Siegfried Line Commission for Organising the Fortified Regions ( CORF ) Notes Footnotes Jump up ^ There are 58 ouvrages, 311 casemates, 78 shelters, 14 observatories and around 4,000 blockhouses on the North - West and 84 ouvrages, 41 casemates, three observatories and around 1,000 blockhouses to the South - West. Citations Jump up ^ Gravett 2007, p. 187. Jump up ^ Chelminski 1997, pp. 90 -- 100. ^ Jump up to : Roth 2010, p. 6. Jump up ^ Kaufmann & Kaufmann 2006, Introduction. Jump up ^ Kaufmann & Kaufmann 2006, p. 5. Jump up ^ Kaufmann & Kaufmann 2006, p. 122. Jump up ^ Romanych & Rupp 2010, p. 8. Jump up ^ Marks 1978, p. 249. Jump up ^ Young 2005, p. 20. Jump up ^ Smith, Audoin - Rouzeau & Becker 2003, p. 11. Jump up ^ Jacobsen 1994, p. 214. Jump up ^ Keylor 2001, p. 121. ^ Jump up to : Keylor 2001, pp. 121 - 122. ^ Jump up to : Keylor 2001, p. 122. ^ Jump up to : Keylor 2001, p. 123. ^ Jump up to : Young 2005, p. 13. Jump up ^ Frieser 2005, p. 88. Jump up ^ Young 2005, p. 36. ^ Jump up to : Young 2005, p. 35. Jump up ^ Young 2005, pp. 35 - 36. Jump up ^ Young 2005, p. 37. ^ Jump up to : Young 2005, p. 40. Jump up ^ Young 2005, p. 33. Jump up ^ Young 2005, pp. 40 - 41. Jump up ^ Allcorn 2003, p. 43. ^ Jump up to : Allcorn 2003, p. 44. Jump up ^ Romanych & Rupp 2010, p. 19. Jump up ^ Nichols 1987, p. 27. Jump up ^ Zaloga 2010, p. ? ?. Jump up ^ Ambrose 2016, p. 386. Jump up ^ Seramour 2007, pp. 86 - 97. Jump up ^ Chelminski 1997, abstract. Jump up ^ Cain 2005, p. ? ?. Jump up ^ Kaufmann & Kaufmann 2006, p. 14. ^ Jump up to : Jackson 2003, pp. 26 - 27. Jump up ^ Kaufmann & Kaufmann 2006, pp. 4, 85 - 86, 88. Jump up ^ Haynes, Gavin ( 25 October 2017 ). `` What 's the stupidest thing a nation has ever done ? ''. Theguardian.com. Retrieved 25 October 2017. Jump up ^ `` Opinion - The difficult truths behind ' Dunkirk ' ''. The Washington Post. Retrieved 25 October 2017. ^ Jump up to : Donnell 2017, p. 4. ^ Jump up to : Donnell 2017, p. 45. Jump up ^ Romanych & Rupp 2010, p. 91. ^ Jump up to : Kaufmann & Kaufmann 2006, p. 182. Jump up ^ Kaufmann & Kaufmann 2006, p. 15. Jump up ^ Jackson 2003, p. 27. Jump up ^ Kaufmann & Kaufmann 2006, pp. 153, 157, 160. Jump up ^ Jackson 2003, p. 221. Jump up ^ Roth 2010, p. 7. Jump up ^ Romanych & Rupp 2010, pp. 91 - 92. Jump up ^ Kaufmann & Kaufmann 2006, p. 180. References Books Allcorn, William ( 2003 ). The Maginot Line 1928 -- 45. Oxford : Osprey Publishing. ISBN 1 - 84176 - 646 - 1. Ambrose, Stephen ( 2016 ) ( 1997 ). Citizen Soldiers : The U.S. Army from the Normandy Beaches to the Bulge to the Surrender of Germany Jun 7, 1994 - May 7, 1945. London : Simon & Schuster. ISBN 978 - 1 - 471 - 15833 - 9. Cain, Syd ( 2005 ). Not Forgetting James Bond. Richmond : Reynolds and Hearn. ISBN 978 - 1 - 905 - 28703 - 1. Donnell, Clayton ( 2017 ). Maginot Line Gun Turrets : And French Gun Turret Development 1880 -- 1940. New Vanguard. Oxford : Osprey Publishing. ISBN 978 - 1 - 47282 - 029 - 7. Frieser, Karl - Heinz ( 2005 ). The Blitzkrieg Legend. Naval Institute Press. ISBN 978 - 1 - 59114 - 294 - 2. Gravett, Christopher ( 2007 ). The History of Castles : Fortifications Around the World. Globe Pequot. OCLC 495191912. Retrieved 19 April 2013. Nichols, Kenneth D. ( 1987 ). The Road to Trinity : A Personal Account of How America 's Nuclear Policies Were Made. New York : William Morrow and Company. ISBN 0 - 688 - 06910 - X. Jackson, Julian ( 2003 ). The Fall of France : The Nazi Invasion of 1940. Oxford : Oxford University Press. ISBN 978 - 0 - 192 - 80550 - 8. Kaufmann, J.E. ; Kaufmann, H.W. ( 2006 ). Fortress France : The Maginot Line and French Defenses in World War II. Mechanicsburg, PA : Stackpole Books. ISBN 0 - 275 - 98345 - 5. Keylor, William ( 2001 ). The Twentieth - Century World. Oxford : Oxford University Press. Romanych, Marc ; Rupp, Martin ( 2010 ). Maginot Line 1940 : Battles on the French Frontier. Oxford : Osprey. ISBN 978 - 1 - 846 - 03499 - 2. Roth, Ariel Ilan ( 2010 ). Leadership in International Relations : The Balance of Power and the Origins of World War II. Palgrave Macmillan. ISBN 978 - 0 - 230 - 10690 - 1. Smith, Leonard ; Audoin - Rouzeau, Steéphane ; Becker, Annette ( 2003 ). France and the Great War, 1914 -- 1918. Cambridge : Cambridge University Press. Young, Robert ( 2005 ). An Uncertain Idea of France. New York : Peter Lang. Zaloga, Steven ( 2010 ). Operation Nordwind 1945 : Hitler 's Last Offensive in the West. Osprey. ISBN 978 - 1 - 84603 - 683 - 5. Journals Chelminski, Rudolph ( 1997 ). `` The Maginot Line '' ( PDF ). Smithsonian : 90 -- 100. Archived from the original ( PDF ) on 2 December 2007. Retrieved 26 June 2012. Marks, Sally ( September 1978 ). `` The Myths of Reparations ''. Central European History. Cambridge University Press. 11 ( 3 ) : 231 -- 255. doi : 10.1017 / s0008938900018707. JSTOR 4545835. Seramour, Michaël ( 2007 ). `` Histoire de la Ligne Maginot de 1945 à nos jours ''. Revue Historique des Armées ( in French ). Revue Historique des Armées ( 247 Le renseignement ) : 86 -- 97. Further reading Mary, Jean - Yves ; Hohnadel, Alain ; Sicard, Jacques. Hommes et Ouvrages de la Ligne Maginot, Tome 1. ( Men and Works of the Maginot Line ). Paris, Histoire & Collections, 2001. ISBN 2 - 908182 - 88 - 2. ( in French ) Mary, Jean - Yves ; Hohnadel, Alain ; Sicard, Jacques. Hommes et Ouvrages de la Ligne Maginot, Tome 2. Paris, Histoire & Collections, 2003. ISBN 2 - 908182 - 97 - 1. ( in French ) Mary, Jean - Yves ; Hohnadel, Alain ; Sicard, Jacques. Hommes et Ouvrages de la Ligne Maginot, Tome 3. Paris, Histoire & Collections, 2003. ISBN 2 - 913903 - 88 - 6. ( in French ) Mary, Jean - Yves ; Hohnadel, Alain ; Sicard, Jacques. Hommes et Ouvrages de la Ligne Maginot, Tome 4 -- La fortification alpine. Paris, Histoire & Collections, 2009. ISBN 978 - 2 - 915239 - 46 - 1. ( in French ) Mary, Jean - Yves ; Hohnadel, Alain ; Sicard, Jacques. Hommes et Ouvrages de la Ligne Maginot, Tome 5. Paris, Histoire & Collections, 2009. ISBN 978 - 2 - 35250 - 127 - 5. ( in French ) Rowe, V. ( 1959 ). The Great Wall of France : The Triumph of the Maginot Line ( 1st ed. ). London : Putnam. OCLC 773604722. Kaufmann, J.E., Kaufmann, H.W., Jancovič - Potočnik, A. and Lang, P. The Maginot Line : History and Guide, Pen and Sword, 2011. ISBN 978 - 1 - 84884 - 068 - 3 External links Wikimedia Commons has media related to Maginot Line. ( in French ) The Maginot Line ( French / English / German / Italian ) ( in French ) Fortress of Schoenenbourg, ( French / English / German / Italian ) The U.S. Army vs. The Maginot Line by Bryan J. Dickerson Maginot Line today ( in Czech ) Armament of Maginot Line ( Czech only ) Maginot Line Ouvrages Fortified Sector of the Escaut Eth Fortified Sector of Maubeuge Les Sarts Bersillies La Salmagne Boussois Fortified Sector of Montmédy La Ferté Chesnois Thonnelle Vélosnes Fortified Sector of the Crusnes Ferme Chappy Fermont Latiremont Mauvais - Bois Bois - du - Four Bréhain Aumetz Fortified Sector of Thionville Rochonvillers Molvange Immerhof Soetrich Bois - Karre Kobenbusch Oberheid Galgenberg Sentzich Métrich Billig Fortified Sector of Boulay Hackenberg Coucou Mont des Welches Michelsberg Hobling Bousse Anzeling Berenbach Bovenberg Denting Village Coume Coume Annexe Nord Coume Coume Annexe Sud Mottenberg Fortified Sector of Faulquemont Kerfent Bambesch Einseling Laudrefang Ouvrage Téting Fortified Sector of the Sarre Haut - Poirier Fortified Sector of Rohrbach Welschhof Rohrbach Simserhof Schiesseck Otterbiel Fortified Sector of the Vosges Grand - Hohékirkel Lembach Four - à - Chaux Fortified Sector of Haguenau Hochwald Schoenenbourg Petit Maginot Line Alpine Line Corsica Defensive Organization of Corsica GND : 4099996 - 8 NARA : 10044433 VIAF : 244107292 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Maginot_Line&oldid=853834446 '' Categories : Maginot Line World War II defensive lines Historic defensive lines Tunnel warfare Separation barriers 20th - century fortifications Hidden categories : Use dmy dates from July 2012 Use British English from March 2013 Articles containing French - language text Wikipedia articles needing clarification from February 2011 CS1 French - language sources ( fr ) Articles with French - language external links Articles with Czech - language external links Wikipedia articles with GND identifiers Wikipedia articles with NARA identifiers Wikipedia articles with VIAF identifiers Talk Contents About Wikipedia Alemannisch Azərbaycanca Беларуская Беларуская ( тарашкевіца ) ‎ Български Bosanski Català Чӑвашла Čeština Dansk Deutsch Eesti Ελληνικά Español Esperanto Euskara فارسی Français Galego 한국어 Հայերեն Hrvatski Bahasa Indonesia Italiano עברית ქართული Latina Latviešu Lëtzebuergesch Lietuvių Magyar Македонски Bahasa Melayu Nederlands 日本 語 Norsk پنجابی Polski Português Română Русский Scots සිංහල Simple English Slovenčina Slovenščina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska தமிழ் ไทย Türkçe Українська Vèneto Tiếng Việt ייִדיש 粵語 中文 51 more Edit links This page was last edited on 7 August 2018, at 07 : 16 ( UTC ). Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: where was the virtually unprotected area where german armies avoided the maginot line
Answer: the Ardennes forest