Fort Eben-Emael, an immense and unique underground complex

The military complex has been dug out of a marl hill.

The floor plan is a triangle with a base measuring 750 m and a height of 950 m. The total area of the military site was 75 hectares, equivalent to 150 football pitches.

The Albert canal, with almost vertical walls 60m high, forms the eastern boundary of the fortress. The River Jeker runs to the north-west and a moat was created by the ground defences of the site, which allowed the entrance to the fort to be built under water.
A dry anti-tank ditch was dug to the south. The ground defences were completed with barbed-wire fences up to 6 m deep and anti-tank obstacles.

The fortress was built to protect the bridges over the River Meuse and the Albert canal in the Visé, Maastricht and Lanaken region and to prevent a German invasion force using the access roads and bridges to the Belgian interior.
Along with 8 of the 12 modernised fortresses built at the end of the 19th century, and 3 new fortresses, Fort Eben-Emael formed part of the Fortified Position of Liège in 1940.

The barracks

Level 0 - 45m below the hill plateau

Behind the high iron gate, the wooden retractable bridge over a 3 m deep pit and a machine gun niche are a heavy armoured door and a decontamination area. After this, a gallery nearly 200 m long provides access to the power plant, the workshops and the underground barracks, designed to house up to 1200 soldiers.

The power plant, the original showers, the kitchen, the water pump, the commandant’s office, the officers’ mess, sleeping quarters for commissioned and non-commissioned officers and quarters for the rank and file soldiers, all restored, take visitors back to the inter-war years of the 20th century.

The infirmary, with an operating theatre and a sterilisation room, equipped the fortress for combat situations.


Level 0 - 45m below the hill plateau

Located in 2 former infirmary rooms, the museum commemorates the spectacular attack on the fortress on 10 May 1940 and the attack on three bridges over the Albert canal to the north of the fortress.

A small museum in old soldiers’ quarters shows visitors what life was like in the valley of the river Geer in 1944/45 and the horrors of the German V1 and V2 flying bombs.


Level 0 - 45m below the hill plateau

There are only three DFS 230 (Deutsche Forschungsanstalt für Segelflug) gliders in museums anywhere in the world.

The DFS 230 glider on display at the fortress has mainly been put together from parts reclaimed from the wreckage of three original gliders. The cockpit and dashboard are completely original and both come from the same aircraft.

The glider was assembled by former German glider pilots under the supervision of its designer, Hans Jacobs, under whose management the DFS 230 was built for the Luftwaffe in 1936. Close co-operation between German and Belgian veterans, with the support of the Belgian Ministry of Defence, allowed the DFS 230 glider to be moved to the fortress in 2008.

Eleven of these DFS 230 gliders carried out a surprise attack on the fortress on 10 May 1940. It was the world’s first ever air-borne command attack.

The galleries

Level 1 - 25m below the hill plateau

A maze of 5 km of underground galleries connects the barracks to the restored command post, the filtration rooms, the air vents, the munitions stores and the 17 bunkers secured by armoured doors. The uphill and downhill corridors are connected to one another by steps and run parallel to the roof of the fortress.

Road signs were installed to show the soldiers in the garrison the way through this underground tunnel system.

The guide leads visitors through part of the illuminated galleries.
A number of themed tours extend into a more remote and unlit section of the galleries.


Level 1 - 25m below the hill plateau

German soldiers placed a hollow charge inside the stairwell of a bunker they had taken. The explosion caused a huge pressure wave, killing four Belgian soldiers and seriously wounding several others.

And this explosion had even more unpleasant consequences.

See the disastrous results of the first use of this new type of explosive, the hollow charge, and be moved by the dramatic story of the young soldiers in the garrison.

The Artillery bunkers

Level 2 - on the hill plateau

On the roof of the fortress and connected to the underground galleries by steps and munitions lifts are four large artillery casemates and three artillery cupolas.

The two undamaged casemates, which can still be visited today, are each equipped with three rapid-fire 75mm guns.
The two artillery cupolas have armour plating 33 cm thick. Each of these also had two 75 mm guns covering a 360° firing arc.
The large armoured artillery cupola is made of 2 layers of chrome-nickel steel creating armour plating 59 cm thick. The entire cupola, comprising both a fixed and a moving turret, weighs 440 tonnes. The two 120 mm guns had a 360° firing arc and a range of up to 17 km.

Different tours allow visitors to discover the various types of bunker and artillery cupola.


Level 2

The upper plateau has a surface area of 45 hectares.
In the early morning of 10 May 1940, 10 gliders landed on the fortress in total silence, taking the garrison completely by surprise.

The site is still military property but is open to the public providing they stay on the marked paths. In 1940 there was no vegetation on the plateau or the escarpments.

During the tour of the upper plateau, the guide will tell you all about the landing of the gliders and the German paratroopers’ attacks on the combat posts.
A walking map of the upper plateau and the various bunkers  is available at the fort’s bookshop.


Level 0, 1 @ 2

Six bunkers intended for close-quarters defense of the fortress are located on and around the hill. There were two canal defense bunkers along the Albert canal, only 1 of which still exists today.

All the defensive bunkers were equipped with 60 mm anti-tank guns, machine guns, searchlights, and observation turrets.
On the roof are two heavy machine gun bunkers, each equipped with three heavy Maxim machine guns.

Some of these defensive bunkers, and the only canal bunker that still exists, can be visited on the themed tours.


10 MAY 1940

At dawn on 10 May 1940, 10 large transport gliders carrying an elite unit of German paratroopers (codename GRANIT) landed on the roof of the fortress.
There was no official declaration of war.

Shortly after landing, an attack group disarmed the air defense machine guns. Most of the observation cupolas, machine gun bunkers, artillery bunkers, and artillery cupolas were neutralized very quickly through the use of a new type of explosive, the hollow charge.

Gliders also landed on three bridges over the Albert canal to the north of the fortress and two major bridges were captured.

Counter-attacks by the Belgian artillery in the fortress failed because of a lack of automatic weapons and training The adverse terrain and regular bombardments by the German Luftwaffe ensured that the German attackers kept the upper hand.
Artillery fire from Fort Pontisse and Fort Barchon in Liège was useless as the German soldiers found cover in the bunkers they had already overcome.

During the night of 10 to 11 May 1940, German ground forces crossed the Albert canal and the fortress was surrounded.

By shortly before midday on 11 May 1940, just two artillery bunkers were still operational and defensive fire was impossible because the observation posts had been neutralized. The defending forces’ situation had become critical. The destructive effect of the new German explosives had destroyed the morale of the garrison. Many soldiers in the garrison were either dead, seriously wounded, or demoralized.

The defenders called a cease-fire and around noon on Saturday 11 May 1940, the fortress surrendered. The fort had been taken by the enemy.


The hollow charge bomb, weighting 12.5 or 50 kg, is filled with explosives, but unlike traditional bombs, the power of the explosive is focused in the hollow section in the middle of the bomb.

As the explosion is concentrated on a single point, a 50 kg hollow charge can penetrate 20 to 25 cm of steel and 35 cm of concrete. A vast quantity of concentrated gas is released during the explosion and, with a heat wave of around 2800° Celsius, this creates a pressure wave that destroys and burns all the material underneath.

The functional principle had been described as early as the late 18th century, but it was not translated into a usable weapon until the late 1930s. (Munroe effect, 1888. First use in 1792).

The attack on Fort Eben-Emael was the first time this new weapon had been used.


The German attack succeeded on various levels.

Not only did it break through the positions on the Albert canal but it was a psychological blow to the Belgians and the Allies and a huge boost for the Germans: the strongest fortress in Europe had been taken in the minimum of time!

The breakthrough also had a wider strategic effect.
As planned by German military command, French and British troops withdrew into the Belgian interior, clearing the way for the German attack through the Ardennes.

The result is well-known: allied troops were surrounded in Belgium and pushed back to Dunkirk and Calais.

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