A tank turret now employed as a fort defense, at the Bolærne fort, Norway. Image credit - Tommy Dildseth CC BY-SA 4.0
A heavily fortified military structure is generally referred to as a bunker. Bunkers have been used throughout history as a means to protect occupants or contents against all manner of threats, like military force, natural disasters, chemicals and radiation.
Likewise, bunkers can also be used to contain dangerous contents, like an ammunition bunker, which is designed to withstand an internal detonation.
Velvet CC BY-SA 4.0
However, the term ‘bunker’ is a relatively new one, first being used by German forces in WWI to describe underground shelters. At this time, the same structures were referred to as ‘dug-outs’ by the British. These were rather primitive in their design, and often built sporadically to suit that site’s particular requirements.
By WW2, the Germans were building significantly more complex and affective shelters, becoming widely known as bunkers. The term was first used by Allied forces in reference to German made fortifications and shelters, but eventually became the ubiquitous term for these types of buildings around the world.
A 150 mm gun emplacement at the Longues-sur-Mere gun battery in Normandy, France.
Today most well protected military buildings are referred to as bunkers, but there are actually a few main types. A bunker is usually an underground structure, while one above ground is generally known as a blockhouse.
Blockhouses have been used for centuries, and incorporate firing slits to repel attackers. Smaller blockhouses are called pillboxes, and usually contain just a few occupants.
As mentioned, bunkers can be used for any number of tasks, and therefore can come in a huge number of shapes and sizes, often unique to its environment, requirements, designers, contents and materials used in its construction.
Some serve as a gun emplacement, protecting the gun and its crew. Nearby to these are often ammunition bunkers that supply the guns. They are usually underground to offer the most protection possible to the explosive contents inside.
Others are living quarters for troops, and can be sealed to keep attackers out. Many more complex bunkers can be self sufficient for a while, with their own generators, food stores and ammunition. Plus elaborate ventilation networks are able to keep gas attacks out.
In WW2, the Germans planned and built a massive amount of bunkers. To make this process easier, they managed to standardize their bunker construction much more than had been seen before with the ‘Regelbau’, German for standard-design.
These standardized bunkers simplified their construction and raw materials required, as well as enabling mass production of furnishings and fittings that were known to fit in place. This allowed Germany to build many high quality bunkers at a great speed.
Below we have compiled a collection of bunkers varying wildly in size, purpose and locations.
Transformer bunker Schlier now used to store agricultural equipment. Image credit – Stefan Krasberger CC BY-SA 4.0
This monstrous structure is the Blockhaus d’Éperlecques, France. It was built by the Germans in WW2 to hold and launch V-2 rockets. The 5 meter thick roof was impenetrable by conventional bombs, but not enough to withstand a hit from the a Tallboy bomb. Image credit – Velvet CC BY-SA 4.0
173,000 bunkers were built in Albania from the 1960s -1980s. Many were these, which were prefabricated and placed in position. They could hold 1 or 2 men. Image credit – Fingalo CC BY-SA 2.0 de
A bunker by Atanasovsko lake, Bulgaria. Image credit – Professor Caretaker CC BY-SA 4.0
A bunker disguised as a civilian building. Image credit – Funkyxian CC BY-SA 4.0
A bunker of the Salpa Line, Finland. Image credit – Janiwiki0 CC BY-SA 4.0
A bunker on the island of Texel, in the Netherlands. Image credit – China Crisis CC BY-SA 2.5
A Bunker wreck in Denmark, Holmsland Klit, seaside.
A Finnish bomb shelter built in the early 1940s. Image credit – ZeroOne CC BY-SA 4.0
A German pill-box at Ostend (Belgium) from the Second World War, part of the Atlantikwall. Image credit – Marc Ryckaert CC BY 3.0
A tank turret now employed as a fort defense, at the Bolærne fort, Norway. Image credit – Tommy Dildseth CC BY-SA 4.0
A WW2 German casemate at Merville Battery, France. Image credit – Pwagenblast CC BY-SA 3.0
A WW2 German observation post on Guernsey. Image credit – Mwiki3101 CC BY-SA 4.0
This pointed WW2 Spitzbunker is a type of air raid shelter. The pointed shape made it hard to detect from the hair, and would deflected falling bombs, which would explode on the ground level where the bunker was thickest. Image credit – Lokilech CC BY-SA 3.0
An Albanian Pike Zjarri bunker being used as a house in 1994. Image credit – Albinfo CC BY 3.0
An enormous casemate at Crisbecq Battery, France. It was partially demolished by Allied forces in WW2 after its capture. Image credit – Xfigpower CC BY-SA 3..0
An ex-Renault R.35 tank turret atop a bunker of the Mont Canisy battery complex in France. Image credit – Pymouss CC BY-SA 4.0
Another cloche on the Maginot Line. One or two are placed on almost every large bunker.
Armored bell at Col de Guensthal near Windstein in the Northern Vosges.
Bunker of the Finnish Salpa Line, built between 1940 -1944, to defend against a potential Soviet invasion. Image credit – Ohikulkijia CC BY-SA 4.0.
Bunker of the Spanish civil war in the city of Santa Pola, Alicante. Image credit – Juan Roberto Arango Tamayo CC BY-SA 3.0
Fire control bunker at Crisbecq Battery, France.
Flakturm IV flak tower, Heiligengeistfeld, Hamburg .
German bunker World War I, south of the Nanosy peninsula, on Lake Narocz (Belarus). Image credit – Haliak CC BY-SA 3.0
German command bunker from WWII near Deurne airfield, Antwerp.
German single person bunker for reconnaissane in the field. Image credit – Neodarkshadow CC BY-SA 3.0
Image credit – Lokilech CC BY-SA 3.0
One man bunkers in Austria. Image credit – Linie29 CC BY-SA 4.0
Originally a 2cm anti aircraft position, the base was modified to take a radar antenna for use by Mirus Battery on Guernsey. Image credit – Mwiki3101 CC BY-SA 4.0
The casemate of the Batterie Todt near Pais de Calais, France. This once housed a 380 mm gun capable of hitting the British coast.
The German ‘G-Tower’ flak tower at Augarten, Vienna. The top of the ‘L-Tower’ is visible to the right.
This iron dome is known as a ‘cloche’, or bell in French. These 20 cm thick armored domes were used to observe and defend key areas of the Maginot Line. Image credit – Florival fr CC BY-SA 3.0
