by J E Kaufmann
Eben Emael was the only Belgian fort with artillery casemates. It was also the only new fort whose subterranean facilities were completely enclosed within its perimeter, surrounded by the canal and an anti-tank wall. With a 1,200 man garrison it was by far the largest Belgian fort. This was also a larger garrison than any ouvrage of the Maginot Line. Another unusual feature of Eben Emael was that two of its combat blocks, Block Canal Sud and Fortin 01, were located outside the defended area. Canal Sud covered the other end of the Albert Canal while Fortin 01, lightly armed, provided observation beyond Lanaye, along the Meuse, and into the Netherlands.
The northern part of the fort was partially covered by woods. Nonetheless, the fort was clearly visible from the air because of the canal and anti-tank ditch. South of the fort, farmers' fields helped highlight the location of the fort from the air. The three dummy cupolas apparently showed up well because the Germans marked them as real on their maps. The other large fort of the PFL I was Battice, only slightly smaller in acreage than Eben Emael, but no less powerful. Although Battice had no artillery casemates, it mounted more turret guns: 2 x twin 120-mm gun turrets and 3 x twin 75-mm gun turrets. It was enclosed by a dry fosse with only one small open side of about 60 meters in length. This section was located inside a railroad cut defended by two coffres on its two ends, and was used as the peacetime entrance. Supply trucks left the main highway and drove about 30 meters into the railroad cut, turned into the fosse, and drove a short distance to the entrance block. In wartime anti-tank obstacles closed the entrance to the fosse.
The tunnel complex went around the fort and also cut across its center. A usine with a group of diesel engines was located near a special chimney that discharged the fumes into the fosse. The command post was near the entrance, and ammunition storage areas were near the blocks. The main subterranean works, located about 50 meters outside the fort's anti-tank ditch, comprised the caserne, similar in many ways to the Eben Emael's. A secondary tunnel about 100 meters long led from the main gallery to the wartime entrance and an air intake block well outside the fort's perimeter. Another air intake also located outside, but on the opposite side of the fort was used as an auxiliary position. The garrison used surface barracks during peacetime like at Eben Emael.
The other two smaller forts had a similar layout. At Battice there were no defensive blocks on the surface, only along the fosse. The armament of Battice was similar to Eben Emael, except that not all of the defensive blocks had 60-mm antitank guns. Some of its cloches mounted a machine gun.
The two small forts of Aubin-Neufchateau and Tancremont (Pepinster) were not as large as Eben Emael and Battice. They were more regularly shaped than the two big forts and were surrounded by a fosse. Tancremont was polygonal in shape with four straight sides, while Neufchateau was triangular. Tancremont had originally been designed to take a 120-mm gun turret, but as a result of cost cutting, it ended up having a block with three cloches for machine guns. Both forts followed the general subterranean plan of Battice with regard to the caserne, usine, entrances, air intakes, and other facilities.
Aubin-Neufchateau had a single and a double coffre that covered the three sides of triangular fosse. A detached coffre outside the fosse covered the entrance to the fort. A central block mounting three 81-mm mortars covered three different directions, and the other two artillery blocks mounted a twin 75-mm gun turret each.
The armament of the small Belgian forts was standardized. At AubinNeufchateau, the 81-mm breech loaded mortars that fired through a well-like position similar to the French Maginot positions were actually of French origin. The Belgian positions were designed to give a 90 degree field of fire instead of the 65 degree attained in the French positions. The defensive blocks, including the entrance block, mounted one to two 47-mm anti-tank guns each and a number of machine guns. Tancremont was similarly equipped. The proposed fort of Sougne- Remouchamps would have had two 75-mm turret gun blocks and a mortar block like these two forts. These smaller forts had garrisons of over 600 men, which was more than many Maginot artillery forts.
If not well designed, the Belgian forts were certainly well protected. Like the French and Germans, the Belgians used up to 3.5 meters of concrete on the walls and roofs of their forts. At some points-near cupolas,for instance-they used up to 4.5 meters of concrete. Their rear walls, no less than 2.75 meters thick, were not made intentionally weaker as in the Maginot Line. In the case of armor, it appears the Belgians attempted to make up for failings of earlier forts with mantles in some places up to 500-mm thick and roofs of 120-mm gun turrets up to 460-mm (two layers of armor). The 75-mm gun turrets had roofs of up to 450-mm of armor, which was greater than the 330-mm used by the French. The cloches had roofs of up to 350-mm of armor, also thicker than most of the French ones. Some cloches were the simple observation type that rose above the roof of a block. The machine gun and 47-mm anti-tank gun cloches were usually designed to be flush with the concrete block roof. Their field of fire cut through the roof in a fan shape. Block C-3, outside the entrance to Aubin-Neufchateau, was very unusual because it was located beyond the perimeter of the fort and had a searchlight cloche and two cloches for 47mm guns. The interior positions of the forts were equipped with girder beams and sand bags that could be used to block the interior armored doors if an enemy penetrated from above. The entrances of the smaller forts were similar to Eben Emael's with its rolling bridge trap. Only Tancremont lacked such a device because it was finished too late to receive this addition.
In addition, the forts' surface was secured by anti-infantry obstacles. Both old and new forts were surrounded by wire obstacles encircling the forts. In the old forts they ran in some depth from the counterscarp along the glacis. The air intake blocks of the new forts also had their own individual wire protection that was not found on combat blocks within the fort's fosse.
Steps were also taken to assure communication with the forts. In addition to underground telephone cables, radios were used, but there is no data available on their effectiveness. Although the guns were mostly Belgian models, much of the optical equipment was French. Each fort could operate independently for several weeks.
Between the forts of the PFL I were the interval positions. Along with the antiinfantry and anti-tank obstacles, 162 bunkers, only 8 with anti-tank guns, closed the intervals. Three of these bunkers were for observation and the remainder mounted machine guns. As in PFL II, light, medium and heavy types were included, although here too only a few were of the heavy type with walls 1.5 meters thick. The bunkers used in both PFLs included the combination anti-tank and machine gun bunkers placed at key points such as bridges and roads. These heavy bunkers were often multi-storied and equipped with a cloche and a searchlight. Their main armament was a 47-mm anti-tank gun and a machine gun, and their garrisons consisted of about fourteen men. The observation bunkers, fewer in number, were equipped with an observation cloche but housed no weapons. An anti-tank barrier consisting of ditches and obstacles ran from the Meuse to Fort Barchon and on to most of the other forts on the bridgehead line.
2. The Namur Defenses
At Namur the Belgian army restored and modernized seven out of nine of the old forts. A bridgehead created at Namur on the right bank of the Meuse was similar to the one at Liege. The army restored fortifications on the left bank, which, in effect, created a ring defense. Namur was primarily a second position against a German penetration through southern Belgium or past Liege. It was also prepared for an attack from the left bank of the Meuse in the event of a French violation of Belgian neutrality. The armament of the old forts was modernized. Although the old 210-mm howitzer gun turrets were not rearmed, initially, 105-mm guns replaced the weapons in the old twin 150-mm gun turrets, but later most were replaced with 75-mm GP guns. A pair of heavy machine guns or two 120-mm mortars replaced the old 120-mm cannons. Other changes, mostly internal, were similar to those made at Liege. The armament of the Namur forts included:
The abandoned forts of Eminer and Cogne
lee, that formed part of the all around defense of Namur, were turned into munitions dumps and given a pair of machine gun positions each.
Over two hundred bunkers completed the defense of the Fortified Position of Namur or PFN, almost the same number as at Liege; however, they covered a smaller area. This meant that the PFN had slightly more depth that the PFL. Its northeastern and southeastern segments actually included a second line. Anti-tank ditches and barriers almost completely encircled the position.
3. The Albert Canal Line
Besides PFL-I, from 1936 until 1939 the Albert Canal Line was the most advanced defensive line and considered the main position for the army field divisions, until it was realized that the French could not help defend it if neutrality were maintained until after Germany attacked. This line linked the PFL to the PFA or Fortified Position of Antwerp and joined the Schelde and Turnhout Canal defense lines near Antwerp to complete a continuous barrier facing the Dutch border.
This line ran along the newly constructed Albert Canal and included bunkers with machine guns and anti-tank guns placed into its embankments. Each bunker covered a large stretch of the canal and, usually, a crossing point as well. A total of more than 200 bunkers were built, over 60 of which were on the Schelde and Turnhout Canals.
The bunker types ranged from light to medium constructions (0.5 to 1.0 meters of concrete thickness), many of which were designed for flanking fires and were placed on the bank where the enemy was expected to appear. Fire from the friendly side was expected to cover these positions because the anti-infantry obstacles did not provide sufficient defense. The bunkers were about 1,200 meters apart, but the army, deciding that they were too far away from each other, began adding additional bunkers just before the war.
Nearby, anti-tank bunkers covered bridges already prepared for demolition. One of the main obstacles used to block these crossings was "Element C" (Elements Cointet invented by French Colonel Cointet) better known as Belgian Gates. These large anti-tank obstacles were rolled into position on wheels that were removed when the gates were locked together.
4. Antwerp's Defenses and the National Redoubt
Less priority was attached to this area because of the experiences of World War I. With the fall of Liege and Namur, this position became almost untenable although it held on for many weeks.
Between the world wars only twenty-two of the original thirty-two forts and redoubts of the outer ring returned to active service. The forts of the inner ring were removed from Antwerp's defenses. Since the Germans had removed most of the 57mm and 75-mm gun turrets and scavenged the remaining turrets in 1917, and the forts of the PFL and PFN had received the bulk of the funds allotted for new turrets, the army replaced the PFA fort's turrets with concrete machine gun positions. The old defenses were not abandoned because they occupied man-made platforms that dominated the level terrain.
From the Schelde River to the Albert Canal, a water filled antitank ditch formed the major obstacle in the PFA. As on the Albert Canal, bunkers using flanking fire covered most of the ditch and were embedded on the enemy side of the canal. The bunkers were of several types.
The army engineers had prepared the canal locks and dikes for demolition to create a zone of inundation in front of the PFA. The south front of the PFA included the Nerthe and Rupel Rivers that flowed into the Schelde. The southern banks of these rivers were marshy and served as a final line of defense since the line of forts ran about 5 km south of these rivers. Other tributaries leading to these rivers added to the forward defense and numerous bunkers were concentrated along them (some as part of the KW Line). Between 1935 and 1937 the army added many double embrasure machine gun bunkers to the PFA.
The PFA consisted of the following: Forts Schelde River to 4 Turnhout Canal (linked by AT ditch) Turnhout Canal to 5 Lierre (linked by AT ditch to the Albert Canal; marshes cover remainder of area to Fort Lierre) Lierre to Mechelen 3 Redoubts Bunker 40 3 2 40+ 100+ 3 (most in KW Line)
The defenses ended near Mechelen with only water barriers covering the remainder of the PFA. Between the town of Lierre and Fort Koninghyndt an anti-tank barrier of Element C formed the most significant obstacle. The Ghent Bridgehead occupied the south side of the Schelde River and was linked up to the PFA by the Schelde and Lys Rivers to form the National Redoubt, but no bunkers were built along those rivers. Over a hundred casemates defended the bridgehead with three special casemates for 75-mm field guns.
5. The KW Line
This line ran from Koningshooikt to Wavre and was later extended to Namur. It was the last of the major fortifications to be erected in Belgium, since it did not begin to go up until 1938. Its main defense was formed by the River Dyle, which, unfortunately, did not run along the entire line. To compensate for the lack of natural obstacles, the army had to set up man-made anti-tank defenses at the point where the river turned away from the line. Over 190 bunkers were built along three lines and more field fortifications added. A line of Belgian Gates between Wavre and Namur, almost completed by May 1940, formed an anti-tank barrier that was, unfortunately, virtually undefended since no bunkers had been built to cover that section.
6. The Coastal Defenses
The coastal defenses consisted of a few defended points and dikes located in the polders behind the coastal sand dunes that were prepared for demolition to inundate the low lying areas. A single battery of four old German 280-mm guns constituted the main defensive artillery. The few installations created by the Germans in the Great War were reactivated.
WEAPONS AND EQUIPMENT
Concrete Triangle Concrete Walls Round Concrete Barrier Concrete pillars AT Rails AT Ditch 3 meters wide and 1.3 meters high (hollow inside) Used near Arlon in south. 1.5-2.0 meters high and 1.2-1.5 meters thick. Used as road blocks. 50 meters in diameter and 2.0 meters high (half beneath the ground). Used in two rows in southern Belgium. Same as the French. 2.0 meters high (half sunk into the ground), but height not as varied as the French. Used at Liege and Namur in five rows. 1.5 meters wide and 1.5 meters deep.
WORLD WAR II
When the war began, Belgium frantically worked to complete the Dyle Line (KW Line) while struggling to remain neutral. A special regiment was assigned to each of the three fortress cities. The army, on the other hand, took up positions near the German border after it mobilized. The 1st Chasseurs Ardennais Division was stationed to the Ardennes, near Arlon, while the 2nd Chasseurs Ardennais Division was located near Huy, on the other side of the Meuse. Between these two divisions stood the 1st Cavalry Division and several cyclist companies armed with 47-mm anti-tank guns. These troops could probably have used the few obstacles and bunkers built in southern Belgium to seriously impede the German advance, but their orders did not call for a protracted resistance. The majority of the Belgian army took up positions along the Albert Canal and near the Dutch border. The King refused to allow the coordination of Belgian defenses with the Allies, so the Belgian army was only able to prepare for delaying action on the advanced positions and then withdraw to the still incomplete KW Line. Furthermore, coordination between the Netherlands and Belgium was also non-existent, which forced Belgium to deploy its army along the border with the Netherlands instead of concentrating it near Liege.
The German assault began on May 10, 1940, when German paratroopers, carried in over 40 gliders from airfields near Cologne, silently approached three key crossings of the Albert Canal and Fort Eben Emael even before the ground invasion began. Meanwhile, another German relief force, consisting of a special company wearing uniforms of the Dutch military police, crossed the Dutch border in an attempt to take the bridges at Maastricht. This contingent was followed by an advance force consisting of an infantry regiment and the 4th Panzer Division.
The assault on Eben Emael was meant to draw the world's attention away from the other, more significant operations. The ploy succeeded beyond expectations since the other operations were barely noticed by the world. There was not even much attention paid to the risky landing of troops
in several light Storch aircraft to capture key points in the Ardennes for the main thrust of the campaign.
The glider-landed paratroopers took the bridges over the Albert Canal at Veldwezelt and Vroenhoven, but the Belgians blew up the bridge at Kanne. The attempt to take the Dutch bridges in Maastricht failed, but the spearhead continued to advance. The special engineer assault group landed on top of Fort Eben Emael taking the garrison by surprise. The Belgians were still preparing the fort for action at the time of the attack, but their biggest problem was a lack of defenses on the fort's surface. The Germans used the new, and still secret, hollow charges designed to penetrate most armor of Eben Emael. Thus the Germans successfully neutralized the key positions on the fort that included most of the artillery turrets and casemates. They encountered little resistance from the two ineffectual infantry blocks on the fort's surface and the Belgian artillery men, who were not trained to engage in infantry combat on the surface. Forts Pontisse, Barchon, and Evegnee pounded the surface of Eben Emael with their 105-mm guns to no avail. By the end of the day the Germans neutralized the fort. They even penetrated one block and descended into the gallery below, causing the garrison to seal the access to the tunnel. Canal Nord temporarily checked the crossing of the Albert Canal by German troops until the evening. By the next day the situation became hopeless as the German troops poured across the Albert Canal. A Belgian relief force had been repelled on the first day and there was little left for the commander of Eben Emael to do but surrender the pride of the Belgian forts.
