Barrier de fer

Plan of the Belfort fixed place as part of the Barrière de fer

The Barrière de fer ( German "Iron Barrier" ), also known as the "Système Séré de Rivières", is a chain of fortress rings built around various cities along the German-French border at the end of the 19th century .

Trigger of the construction

France had long adhered to traditional fortress construction based on Vauban's principles. From 1831 to 1852 Lyon and from 1840 to 1846 Paris were fortified with new type of fortification belts with outer forts, and in 1867 the fortifications of Metz , Belfort and Langres began to be expanded . During the Franco-Prussian War of 1870/71, parts of Lorraine and Alsace with the fortresses of Metz and Strasbourg fell to the newly founded German Empire . This prompted the French government in the 1870s and 1880s to fortify a new line along the French eastern border. General Séré de Rivières was entrusted with the implementation of the project .

This armor efforts have been favored by a then popular in France revanchism (fr. Revanchisme ), an up to the First World War widespread nationalist current that the reconquest of Alsace-Lorraine was aimed.

French and German maps of the fortifications
French map from 1907 with the fixed places (camps retranchés - places fortes).
German map from 1887 with the drawing of the French forts.

France had the new Chassepot rifle and the Mitrailleuse machine gun during the war of 1870/71 . They were superior to the Prussian breech loading needle guns in terms of range and rate of fire ( cadence ). These advantages hardly came into play, however, because the steel breech- loading guns from Alfred Krupp - for example the latest model with the type designation C / 64/67 - were far superior to the French artillery . The battle of Sedan on September 1, 1870 in particular showed that its high rate of fire (up to ten rounds per minute), together with a long range (maximum 3,450 m) with good accuracy, had a devastating effect. The French armies were mostly encompassed and forced to withdraw, some of them precipitous, or surrender.

Many French believed that fortresses (from which one could shoot a larger area than before with the better weapons mentioned above) were a strong defense.

In the 1890s, new explosive shells appeared; these had a much stronger explosive effect than the artillery ammunition used until then. They were able to shoot together masonry fortifications piece by piece, as was shown, for example, by the siege of Maubeuge in 1914 , which ended after two weeks with the surrender of the fortress.

decision

In 1873 the last German occupation troops left France. On July 28, 1872, the Comité de Défense was founded according to a décret présidentiel . It met from 1872 to 1888. Its task was the "réorganisation défensive" of all - maritime and terrestrial - borders of France. When it was founded, it had nine members, including the Minister of War, representatives of the artillery and military engineers ( Génie militaire ).

The breach created by the loss of fortresses in the northeast was to be closed and the old squares, which had proven outdated in 1870, modernized. In addition, new places should be found that were suitable in view of new war techniques and, above all, the great advances in artillery.

General Séré de Rivières , Commandant du génie des 2 ^e corps d'armée de Versailles , was one of the founding members and was appointed secretary of the committee in 1873 . On February 1, 1874, he became head of the Service du génie in the War Ministry. During these years he was the driving force behind the committee and had all the power necessary to get his ideas approved and implemented - with no real opposition.

Course of the line

The series of fortresses and fortress belts included

a northern part - starting from the North Sea along the Belgian border and the historical border with Lorraine and Alsace to the Swiss border in the Belfort area ;
a southern part on the border with Italy: in the Maritime Alps from the Swiss border to the Mediterranean near Nice

Structure of the line

Basically, old fortress, garrison and / or transit cities such as Fester Platz Verdun , Fester Platz Toul , Fester Platz Épinal , Laon , Fester Platz Belfort , Nancy , Reims ( Fort de la Pompelle ) etc. were given a ring of forts , Intermediate works , infantry works ( Ouvrages and Ouvrages d'infanterie ) and temporarily stored batteries. As a rule, the individual systems were connected to as many subsequent systems as possible by visual contact for communication via light signals. Between the facilities themselves and the city surrounded by the belt, there was a - often well-developed - light rail network . Between the larger fortress rings, forts and intermediate works were also built at different distances, mostly in visual contact with the neighboring facilities. In individual cases, entire localities were developed into defenses because of their favorable location, Villey-le-Sec near Toul is an impressive example.

Three types of construction

There are three types:

fort d'arrêt (9 in the north, 2 in the south-east) (= Sperrfort)

fort de rideau (or fort de liaison ) (= line fort or connecting fort )

fort de place (or fort de ceinture ) (= fort of a fortress belt)

In addition, a distinction can be made between forts that kept their original state and those that were subsequently strengthened.

The fort d'arrêt was often a large fort. It was by definition isolated from the rest of the system. It therefore had to be completely autonomous and self-sufficient and able to defend itself on its own; it had to shoot in all directions. It was designed to slow the advance of enemy forces so that French troops could buy time to create a new line of defense.

The other two fort types could count on the help of their neighboring forts and did not need to defend themselves all around, but only to one side. The artillery was concentrated on this side.

With regard to the location in the area, three types can also be distinguished:

massive fort and artillery close to the ground
Artillery high above the ground
flat fort (on a ridge - especially Fort d'Uxegney )

A large fort cost 2 to 2.5 million Francs d'Or ; a secondary one about 1.5 million.

Modernization / reinforcement

When new explosives were discovered and used in the explosive grenades mentioned - above all picric acid (TNP), the forerunner of TNT - this was called La crise de l'obus torpille in France , and explosive grenade crisis in Germany . The French army bombarded Fort de la Malmaison on a test basis in 1886 and found that practically every brickwork was damaged or destroyed. The forts considered most important were modernized. In some places slabs of hard concrete were poured; in some cases barracks were built entirely of concrete, with the old masonry left standing next to it. The tests had also shown that the powder and ammunition magazines were no longer safe. New ones were built deeper underground (called magasin sous roc or magasin caverne ); Another option was to store the ammunition distributed throughout the buildings.

Some forts received new entrances that were deeper (in the trenches) and were better protected against fire ( entrées de guerre ).

All modernized forts also received their own generators to generate electricity.

Armored turret "Tourelle de 155 C"

The lookouts at the forts looked like large concrete bells. There were also small towers for machine guns and for projecteurs . Many armored domes were retractable.

Last work during the battles

With the exception of the Battle of Verdun , only a few forts of the Barrière de Fer took part in the fighting. The soldiers, who were exposed to barrage from bullets in the older forts of Verdun , feared for the resistance of the concrete and began to bury themselves. They dug deep and spacious networks of galleries and rooms under the forts. On this occasion they also built new exits - further back and less exposed - and new combat positions, especially lightly armored casemates for machine guns. This work was called travaux de 17 (because most of them took place in 1917). They anticipated developments in fortress construction that were later found in the Maginot Line in 1930 .

Significance in the First World War

In contrast to the Second World War , the German advance was very much entangled in the fortress ring and led to battles like the one around Verdun . In many other places, too, the German troops were only able to penetrate the first strip of the fortifications. A rapid advance, such as against the Belgian installations in the course of the Schlieffen Plan and their removal, could not be carried out because initially only weak associations were attacked. Later on, the increasing shortage of materials was particularly noticeable on the German side, although the French plants were partially decommissioned and even disarmed.

Meaning between the wars

After the capitulation of the German Reich and the Treaty of Versailles , most of the systems were dismantled or used as material stores. Metals in particular were in short supply after the war and considerable quantities of these were used in the plants.

Significance in World War II

Some of the facilities were used again as a second line or barracks. However, most of them were so badly damaged by the bombardment in World War I that they could no longer be used. However, there are several exceptions, such as Fort d'Uxegney , which is still in good condition, or Fort de Seclin in Seclin : the latter served German troops as barracks and army headquarters during World War II.

today

Many systems still exist today. Some are released for viewing by the owners or sponsoring associations, the latter in particular also offer guided tours. Many, however, are privately owned or on military grounds, and a visit should always be preceded by permission from the owner. Some are used as targets for artillery and infantry exercises or, in Champagne, also as wine cellars. There is a museum in the Fort de Seclin .