Stp Tintenfisch (Ostende - 013)
Belgian naval base/COMOPSNAV/COMLOGNAV/
Mine Warfare School EGUERMIN (Cold War/present)

Map number



This strongpoint is located within the grounds of the Belgian naval base and mine warfare school EGUERMIN. The postal address is 3e & 23ste Linieregimentsplein in Oostende. The base is called Kwartier Bootsman Jonson.

Tactical function

Kriegsmarine barracks
Unit(s) 8.40 - 15.01.1942
Marinehafenabteilung Ostende
15.01.1942 - 01-07.1943
3. Flotillenstammabteilung/1. Flotillenstammregiment/Admiral der Seebefehlsstellen
01.07.1943 - 9.44
? (possibly Hafenschutzflotille or Marinebauaufsicht/Hafenbauamt)
Troops No exact information available


No exact information available


,R502, Luftschutz bunker
Remaining bunkers ,R502, Luftschutz bunker
Radar -
Comments This location actually has quite a unique character, largely maintained by the Belgian navy. The massive air-raid bunker is a unique are extremely rare remnant and many  doors, armoured plats and items of ventiation equipment of the R502 are still original and in working order.
This location also has a rich post-war history. In the period 1945-1976 Ostend was the most important naval base of the Belgian navy. In the period 1946-1981 it was the headquarters of COMOPSNAV, i.e. the operational navy command, while in the period 1953-1999 it was also the headquarters of COMLOGNAV, the logistics commad of the Belgian navy. Since 1958 it has been the home of the Naval Mine Warfare School, later called Belgian-Netherlands Mine Warfare School and now called EGUERMIN.
During the Cold War the R502 was used for ammunition storage, while the Luftschutz bunker was used as a telephone exchange.
We want to thank the Belgian Naval Component and the Kwartier Bootsman Jonsen for their offcial permission to enter the base and visit the bunkers in 2013, with special thanks to the MAD at the time, who acted as our very enthusiastic guide.


See this strongpoint on Google Earth

Yellow indicates existing constructions
Red indicates
disappeared or more or less invisible constructions. Some positions may be approximate only.
The two-part armoured d
Below are some impressions of this strongpoint
The numbers below refer to the above Google Earth map
1. Luftschutz bunker
The LS-Bunker is a massive and rare construction. Its presence on (ex)-military terrain and its planned use as an archive location for the city of Ostend has and will guarantee its survival. The dimensions of the bunker are 68x8.5 metres, with walls of at least 1.5 metres. The shape of the roof was designed ti minimise the chances of a direct hit.
Constructed by the Germans the bunker was used by the Belgian navy during the cold war, of which we see a first indication above the entrance.
Let's enter the bunker
The bunker has 4 entrances each of which was protected by an armoured door,
which is stilll present.
Plan of the ground floor of the bunker 
The entrance corridor seen from 2 directions
At the other end of the corridor we find the entrance to the bathroom.
Quod erat demonstrandum
Little niches at the back of the bunker
We now enter the actual shelter room
The large shelter room. In a recent past the room was used as a dressing room for secondary school students. This explains the presence of coat hangers on the walls. The boxes spread across the floor contained duffelcoats, steel helmets and rubber boots, as indicated by the text written on them.
At the eastern end of the bunker we can still find the telephone room as used during the Cold War. Here we see the entrance to the room
The outside of the room with the small openings
Inside the room. Note the information on the blackboard? No-one has bothered to wipe off the information written down on it during an exercise.
We now take the staits leading to the first floor.
View of the first floor of the bunker.
The staircase down to the ground floor at the other end
Let's now walk towards the other (eastern) end of the bunker
Again we can see how massive the bunker is, the biggest bunker in Belgium
The entrance at this end
The armoured door is present here as well.
This end of the bunker is, amonst others, taken up by the heating, electrical and ventilation systems of the bunker. From here on one can proceed either on the left or on the right side of the bunker.
We start by exploring the right-hand side. This side was actually not meant for walking, so we had to crawl underneath the cables and pipes to reach this part.
There is a long corridor at this end. This picture also clearly shows that the bunker consisted of an inner and an outer wall in order to better absorp the power of a bomb hit.
We now go back to the entrance and explore the left-hand side.
In this corridor we find the telephone exchange equipment
We tried but were unable to reach anybody.
The end of the corridor is in sight, but there are further rooms to the right.
The first of these small rooms
Another room with telephone equipment everywhere
The end of this corridor but a passage takes us anew to the right-hand side of the bunker.
Here, the passage we were in earlier is continued
We now go back and see a green-coloured ladder on our left. This ladder leads to 2 small rooms on the first floor
The two rooms with the partition in the middle.
2. R502
The Belgian military base also houses an R502.
The above pictures show the outside of this bunker
Time to enter the bunker
The entrance corridor with the Verteidigungsscharte
Two examples of the two-part armoured doors type 434 PO1 are still present in the bunker and in very good condition. This is one of these doors.
What is even more amazing is the presence of 2 original Gittertüre type 491 P02. These originally closed off the entrance to the entrance corridor.
Equally remarkable, the presence of the armoured plate type 483 P2 of the Eingangsverteidigung.
View into the gas lock
We first walk towards the other entrance.
Here, too, the armoured plate type 483 P2 of the Eingangsverteidigung is still present...
... as is the second two-part armoured door type 434 PO1 maintained in perfect working order by the military.
Here we also find the second Gittertür type 491 P02.
This one is actually still firmly lodged into the side walls.
Before entering the crew room we see an Ûberdrückventil
complete and in perfect working order
The original parts simply overwhelm you in this bunker. This is the original gas-tight door 19P7 closing off access to the crew rooms. Again, the door is in perfect working order.
View into the left-hand side crew room. The painted text on the wall reminds us that the bunker was used by the Belgian navy to store ammunition (both live and practice).
More original parts: a complete Überdrückventil on the left and an air inlet in the middle. On the right we see an incomplete pressure valve
Marks on the wall show where the room filter hung.
Inside view of the armoured plate of the Eingangsverteidigung
The water evacuation hole was closed up.
The wooden ceiling
We now move into the second crew room.
Note the incomplete air inlet on the far-right picture.
Yet another complete pressure valve here
Remains of cables
Broken off part of a pressure valve
View inside the periscope room of the R502
In this small observation room we find one ventilation pipe in very good condition, a niche, and an Überdrückventil
3. Mine Warfare School EGUERMIN
The Kwartier Bootsman Jonsen naval base today houses the Belgian-Netherlands Mine Warfare School, now known as Eguermin (Ecole de Guerre contre les Mines)
The officers' mess was one of the last achievements of the famous Bruges architect Louis Delacenserie. Until WWII the 3rd Belgian Line Regiment was quartered here. This regiment was disbanded after the war. The barracks were renamed Generaal Mahieukazerne and used by the Belgian navy. In 1972 the name was finally changed into the Kazerne Bootsman Jonson, after the Antwerp-born Jonson, who in 1941 joined the military in London and became a member of the Belgian section of the Royal Navy