Since the days of Antiquity and the Middle Ages, people have become accustomed to defending themselves with fortresses. Well, those who came to fight tried to take these fortresses, and not leave them in the rear, even if their offensive was developing successfully. There were always those who fought for fortified points and those who considered them an obsolete phenomenon of the past. Well, and the First World War in this regard was especially indicative. In it, they carried out wide roundabout maneuvers, and for months besieged and stormed the fortified forts. However, the story of the forts should begin with a story about people, or rather about one person who almost defeated France at the very beginning of this war!
Alfred von Schlieffen was born in Berlin in 1833. He was a graduate of the Berlin Military Academy in 1861 and served as a staff officer during the Austro-Prussian War. In 1891 he succeeded Helmut von Moltke as chief of the German General Staff. At the time, the German high command feared that a resurgent France, wanting to reclaim territories lost in the Franco-Prussian War of 1870, and Russia would unite to attack Germany. His main concern was to develop a plan that would allow him to fight against Russia in the east and against France in the west at the same time. Four years later, he developed a plan called the Schlieffen Plan.
It was a strategy of preemptive invasion of Belgium and the Netherlands, followed by a flanking movement to the south to cut off Paris from the sea (I remember 1940, too, isn't it?). This plan was not implemented in 1905, but British intelligence became aware of it. A secret diplomatic note was sent to Germany, making it clear to the German government that an invasion of neutral Belgium would lead to a declaration of war by Great Britain. Then Germany did not yet feel strong enough to fight Britain, France and Russia, and the "Schlieffen Plan" was frozen. In 1906, Alfred von Schlieffen resigned and died in 1913.
However, then this plan was revised and adopted as a basis. In 1914, Germany was already ready (that's how quickly her military power grew!) To strike at France. However, on the way to the capital of France, there were a number of fortifications. Inevitably, it was necessary to attack Liège and Namur, and then, after the defeat of their forts, use the Belgian roads and railways to quickly move troops in Northern France and west of Paris to encircle the French army before it was fully mobilized.
However, Liege was a tough nut to crack. It was defended by twelve forts arranged clockwise around it. The old Citadel and the outdated Fort Chartreuse defended Liege itself. The fortresses in the outer ring were built in the 1880s, when the largest siege guns had a caliber of 210 mm. The forts had only a handful of large-caliber guns ranging from 120mm to 210mm, complemented by a number of 57mm rapid-fire cannons, and the concrete floors were designed to be able to withstand shells from 210mm siege cannons and nothing more. But it was believed that, in general, the fortress was well fortified, had enough troops and weapons, and could keep the Germans at Liege for a long time. However, despite all the efforts of the commandant of the fortress, Lieutenant-General Gerard Lehman, undertaken by him with the beginning of hostilities, she also had quite obvious shortcomings that could no longer be corrected. So the distances between the forts, although they were covered by the infantry, but the trenches for it were not dug, and the work had to be done urgently and in an extremely short time. As a result, the defensive lines of the Belgian troops were unable to resist the Germans here.
The battles to capture the fortifications of Liege continued from August 4 to August 16. The German army launched an offensive against Liege on August 4, 1914. At this time, the heavy siege weapons had not yet reached the front, but the field guns had already opened fire on them. On the night of August 5-6, the Germans launched a night attack, but the Belgian garrison repulsed it and inflicted significant losses on the Germans. On the 7th Ludendorff, then still a communications officer, found the 14th brigade without a commander and took command over it. He noticed that the Belgian forts were located so that they could not effectively support each other, after which his soldiers penetrated between Fort Eugene and Fort Aileron with little resistance.
After that, Ludendorff moved to Liege, which had just been bombed by the German Zeppelins. The obsolete Citadel and Fort Chartreuse were taken, and after them the German troops entered Liege itself. But the rest of the forts of Liege still had to be taken, since they dominated the territory along the railway.
The infantry attack on the fort of the city of Barkhon on August 8 was repulsed, but the second attack on the 10th on the neighboring fort was successful. Fort Aileron remained intact, but could not operate effectively, as the canopy of the main battery gun's lifting mechanism was jammed. German heavy artillery arrived at the position on August 12th and it was an impressive force: 420mm Krupp howitzers and 305mm Skoda howitzers. By 12.30 on 13 August, the fortifications of Fort Pontiss were crushed into rubble.
Three types of projectiles were used, and they all had tremendous destructive power. So, a high-explosive projectile, when it exploded, formed a crater with a depth of 4, 25 meters and a diameter of 10, 5 meters. A shrapnel projectile gave 15 thousand fragments, which retained their lethal force at a distance of up to two kilometers. Armor-piercing shells (or "fortress killers" as the Germans called them) pierced two-meter concrete floors. True, the accuracy of the fire was low. For example, during the shelling of Fort Wilheim on 556 shots, there were only 30 hits, that is, only 5.5%. A Skoda mortar shell pierced two meters of concrete. The funnel from the rupture had 5 - 8 meters in diameter, and the fragments from the explosion could penetrate solid shelters at a distance of up to 100 meters, and with fragments hit manpower within 400 meters.
In the next two days, the same fate befell six more forts, including Fort Aileron. The Germans suggested that the defenders of the remaining forts surrender, arguing that their position was hopeless. However, the Belgians refused to surrender. Then the Germans began shelling and for 2 hours and 20 minutes their 420-mm guns fired at the forts. The shells pierced the concrete floors and exploded inside, destroying all living things. As a result, the two remaining unfired forts simply surrendered.
Only one of the forts killed more than 350 people, that is, more than half of the garrison remained buried in ruins, which are still considered a military burial. By August 16, the Germans had taken all the forts except Lonseng. But then, during the bombing on it, an ammunition depot exploded, after which the Germans managed to break in. General Lehman was found unconscious and taken prisoner, but out of respect for his courage, they were allowed to keep their saber.
The ease with which the Belgian forts were taken by the German troops in many respects, as it turned out when studying the consequences of the shelling in the future, was due to the fact that concrete was used on them without reinforcement. In addition, it was poured in layers, not a monolith, which created many weak points in the overall structure of concrete casting. Similar shortcomings took place on the fortifications of Port Arthur. So, although reinforced concrete was already known at that time, it was here, on the forts of Liege, it simply was not there, which allowed German shells to penetrate even the thick arches of concrete casemates with great ease.
However, there is never a silver lining. The ease with which the Germans took these forts gave them a false impression of the ease with which modern forts could be overcome, leading to a more than optimistic view of the cost and likelihood of success of the Verdun offensive in 1916. Of course, the Germans expected to take Belgium faster than they did and the delay, no matter how short, still gave the French government time to mobilize and deploy its army.
