The Seeko headquarters in turn controlled a variety of naval units in their sector. The most important were the harbor commands with a Hako (Hafenkommandant: port commander) in the larger ports and a Haka (Hafenkapitän: harbor captain) in the smaller ports. These commands usually included a port police force (Hafenüberwachung). The Kriegsmarine had an active program for using naval mines for coastal defense, but this subject is largely outside the scope of this book. Of somewhat more relevance are controlled mines for harbor defense. The raids on St. Nazaire and Dieppe made it quite clear that existing net and boom harbor defenses were inadequate and led to further examination of controlled mines for harbor defense, a tactic previously shunned by the Kriegsmarine in France. Controlled minefields were left inactive to permit friendly vessels to pass, but could be made active in the event of a raid to protect the harbor. The standard types in German service were modifications of existing naval mines such as the RMA, RMB, RMH and KMB but fitted with a remote activation device and tethered by a submarine cable which led back to a mine control station in the port. These mines were eventually deployed in a number of French harbors, but a shortage of mines led to the local development of the so-called Franz WB (Französische Wasser-Bombe: French depth charge) using captured stocks of French depth charges. These controlled mine units were also responsible for the deployment of harbor demolition mines, which were used in several ports, such as Cherbourg, St. Malo and Brest, to wreck vital equipment prior to the surrender of the ports to the Allies.
German coastal defense doctrine placed considerable importance on light coastal forces such as torpedo boats and small submarines and these were under the control of Defense Command-West (Befelshaber der Sicherung West) with three defense divisions (Sicherungs Division) in French waters, the 2.Sicherungs Division on the Channel, the 3.Sicherungs Division from Brittany to the Loire estuary, and the 4.Sicherungs Division on the Atlantic coast. These naval forces are outside the scope of this book.
From a coastal fortification standpoint, the most significant units were the coastal artillery battalions. There were three principal types, the Marine-Artillerie-Abteilung (MAA), the leichte Marine-Artillerie-Abteilung (leMAA: light naval artillery regiment) and the Marine-Flak-Brigade (MaFl-Br). Each naval artillery regiment consisted of several gun batteries, each battery deployed at a single coastal artillery post with several guns, a fire-control bunker and associated defensive and support positions. There were 14 regiments along the Atlantic Wall in France plus two more (MAA.604 and 605) on the Channel Islands. The light naval artillery battalions were peculiar to the Atlantic coast islands and were hybrid formations consisting of a few gun batteries and a few companies of naval infantry for island defense. The navy Flak brigades, as their name implies, controlled major port anti-aircraft sites. There were three of these: III.MaFl-Br at Brest; IV.MaFl-Br at Lorient; and V.MaFl-Br at Saint-Nazaire.
The heights of Cap Blanc-Nez overlooked the cliffs of Dover across the English Channel and so were the site of several observation posts like this one and two other examples further down the slope. (Author’s collection)
One approach to coastal defense rarely used on the Atlantic Wall in France was the shore-based torpedo battery. The Kreigsmarine was made painfully aware of the capabilities of such batteries with the loss of warships in the 1940 Norwegian campaign, and developed a shore-based version of the standard TR 53.3 Einzel launcher from the S.Boote torpedo boat, which fired the 533mm G7a torpedo. However, these weapons were expensive and not as well suited to the open coastline of France as the constricted fjords of Scandinavia. The only significant use of shore-based torpedo stations in France was around the harbor of Brest where batteries were installed in 1942 near Crozon Island at Fort Robert and Cornouaille Point.
Batterie Lindemann
The Schleswig-Holstein battery armed with three Krupp 406mm SKC/34 guns was originally installed on the Hel Peninsula near Danzig but in early 1941 the Kriegsmarine decided to redeploy these guns to the Pas-de-Calais. The site selected for the new battery was Noires-Mottes, located between Cap Blanc-Nez and the coastal town of Sangatte. Each casemate consumed some 17,000m³ of concrete and the guns were mounted in fully armored Schiessgerüst C/39 turrets. They were entirely self-contained with their own power generation and ammunition magazines. The three guns were directed by a massive fire-control bunker based on the S100 type, which included a large Lange optical rangefinder and was supported by a Würzburg See-Reise FuMO 214 surface-search radar located nearby on Cap Blanc-Nez, as well as several other observation and range-finding posts.
These guns had originally been designed to arm a new class of battleship that was never built. The massive casemates for the guns were the S262 types, measuring about 50m in length and 17m in height. The three casemates were named Anton, Bruno and Cäsar. Anton and Cäsar became operational in June 1942 and Bruno in July, but at this stage their full concrete casemate had not been completed. They did not begin any major bombardment of the English coast until November 1942. The battery was initially named Grossdeutschland and was part of StP Neuss. It was manned by MAA.244 and commanded by Kapitänleutnant MA Werner Lokau. In September 1942, the battery was renamed after the captain of the ill-fated battleship Bismarck, Ernst Lindemann.
In total, the three guns of the battery fired 2,450 rounds including 1,242 against coastal traffic, 593 against English ports, 235 against the city of Dover, 186 against British coastal batteries and 194 against unrecorded targets. Batterie Lindemann was a frequent target of British air-raids as well as counter-battery fire by British coastal guns and over 1,600 impacts were recorded in its perimeter, with about 45 hitting the gun casemates. The attacks left the terrain around the batteries a lunar landscape but failed to damage the gun casemates, and only two personnel were killed in the three years of counter-bombardments. The Canadian North Shore Regiment finally captured the battery on September 25, 1944. A half-century later, the casemates were submerged under spoil and an artificial pond created from the construction of the Eurotunnel, which runs directly under the site. (Artwork by Lee Ray)
The most technologically advanced naval fortification on the Atlantic Wall was this experimental turret for a 150mm SK C/28 gun located in the coastal marshes near Fort Vert east of Calais. The turret used stressed steel wire instead of rebar to reduce the weight of the turret and it was fully traversable using a warship-type race. As a result, it was able to turn landward to fire on approaching Canadian troops in September 1944, and the turret remains locked in this position today. The fire-control post in the background served the nearby MKB Oldenburg. (Author’s collection)
German Army defenses in France
Until 1943, the areas between the ports were much less heavily defended than the ports. The naval coastal artillery batteries tended to be clustered around the key ports, leaving significant expanses of coastline without any protection. These were gradually covered by army coastal artillery batteries deployed along the coast like “a string of pearls” to provide a basic defensive barrier. Coastal artillery was viewed as an excellent expedient since a single battery could cover about 10km of coastline to either side of the battery. In addition, the resources needed were fairly modest since most of the batteries were created using captured French, Russian or other weapons. As in the case of other defenses, the army’s coastal batteries were most heavily deployed along the Pas-de-Calais and Upper Normandy in the Fifteenth Army sector, with an average density of one battery every 28km, while in the Seventh Army sector from Lower Normandy around the Cotentin Peninsula, the density was only one battery every 87km. As can be seen from the charts below, the Fifteenth Army had nearly double the density of artillery of the other two sectors, averaging nearly one gun per kilometer. This certainly did not live up to the propaganda image of the Atlantic Wall. German tactical doctrine recommended a divisional frontage of 6 to 10km, implying a density of about five to eight guns per kilometer, substantially more than average Atlantic Wall densities.