Lorient, France

The U-boat bunkers in Lorient

Before the great Keroman shelters was built, there were built two so called Dombunker (cathedral shelter). The were named East and West bunker. They gave only place for one U-boat and were 81 m long, 16 m wide and 25 m high.

The construction of the first shelter, Keroman I, began on 2 February, 1941, followed by Keroman II three months later. The Keroman III , the largest at 24,000 square meters construction started in October 1941 and it became available at the beginning of 1943 and fully operational in May that year.

Keroman I was 119,5 m long, 85 m wide and 18.5 m high. It housed 5 pens numbered K1 to K5. The roof was originally 3.5 m thick

Keroman II was 128 m long, 138 m wide and 18.5 m high. It housed 7 pens numbered K6 to K12 plus an eighth pen called K6A next to K6. The roof was originally 3.5 m thick

Keroman III was 138 m long, 170 m wide and 20 m high. It housed 7 pens numbered K6 to K12 plus an eighth pen called K6A next to K6. The roof was 6.4 m thick in some places and 7.4 in others.

6 bunkers were built to the north-west of the Keroman area which housed the torpedo storage needed for the U-boat force.

The three Keroman bunkers. At first Keroman III, behind Keroman I and then KeromanII. In the circle the East Dombunker

After the war

Today it seems as if the Keroman base will be sold. Then it will be up to the owner what will happen to the facilities. History has told us that scrapping is the traditional way under these circumstances.

Kernével

From left to right: Villa Kerozen, Villa Kerillon and Villa Margaret.

Admiral Karl Dönitz's new BdU headquarters at the Villa Kerillon at Kernéval in Lorient was officially made operational at 0900hrs on 11 November 1940. It was an inspired choice, the middle of three villas standing on the western bank of the Ter River facing the foreshore of Keroman, commonly known as the 'Chateau de Ter'. The construction of the three villas had been completed during the second half of the nineteenth century, a testament to the success of shipowners involved in the Breton Sardine fishing trade (hence Dönitz's headquarters being soon renamed 'le Chateau des Sardines' by his staff). To left and right the remaining villas, Margaret and Kerozen, housed the many officers that toiled in Dönitz's tightly run command post. The 'Lion' would now be on hand to interact with his officers and men and able to obtain a more personal feel for the fortunes of the German Atlantic war.

In 1940 before the arrival of German troops, Lorient, which lay on the Western bank of the River Scorff, was part of the 5^th Naval Region, the seaward approaches to its entrance channels guarded by the slender Ile de Groix. This city’s Préfet Maritime was Vice Admiral d’Escadre de Penfentenyo de Kerveguer, Lorient itself commanded by sector commandant C V Labourer. On 1^st September 1939 in Brest, Lorient and Saint-Nazaire there were created Centres d’Armement Militaire des Bâtiments de Commerce that proceeded, eight days later, to arm merchant ships for the threatened convoy war. Many were also to be converted into auxiliary warships. Beginning in 1930 the French Commander-in-Chief of the Navy had drawn up a plan of requisitioning whereby the navy had free reign to decide which vessels were suitable for conversion to auxiliary military use. Those designated as auxiliary naval vessels were given a military number prefixed with a letter: X for Auxiliary Cruisers (X1-X22) and Specialist Ships (X23-X84). Specialist ships included such vessels as cable layers, hospital ships, colliers, submarine tenders and mine layers.); P for Patrol Boats; AD for Minesweepers; VP for small port security vessels. However, the French collapse of June 1940 brought German troops racing towards the French Atlantic coast.At Lorient on 18th June 1940, a total of fifteen French warships and thirty-five smaller vessels left the harbour, bound for England or North Africa. Only a single vessel was lost to enemy action. This ship, the large trawler La Tanche of Fécamp, struck a German mine and sank 150 metres West of the Truies buoy marking the entrance to Lorient. She was carrying nearly 200 people as well as a 30-man crew. Among her passengers were Polish soldiers, French airmen, mechanic apprentices and several of the French sailors’ wives and children. The explosion was so violent that she sank in seconds and only twelve people were rescued. After the remainder of the evacuation was completed without further incident the port was declared an open city and surrendered by Admiral Hervé de Penfentényo de Kervériguin on the 21^st June. At 1400hrs the first German troops entered the sullen outskirts of Lorient.

Lorient immediatley had a Kriegsmarinewerft installed under the direction of Korvettenkapitan Waldemar Seidel, commandant of the Lorient Arsenal, as did Saint-Nazaire and other German military ports further to the South. Units of Netzsperrflotille West provided protection from submarine attack before both Brest and Lorient. Anchored in place and suspended from large buoys these thick steel mesh anti-submarine nets stretched across the entrance channels to both ports, moved aside by steam tugboats to allow vessels free transit between port and open sea.

Lorient saw the arrival of 2^nd U-Flotille “Saltzwedel”, commanded by Korvettenkapitän Heinz Fischer, from Wilhelmshaven in June 1940. The first boat to arrive was, Kapitänleutnant Fritz-Julius Lemp’s U30 (of Athenia infamy) on 7th July 1940, making Lorient the first fully operational Atlantic U-boat base. German engineers of the M.A.N. Mascchinen Fabrik arrived to work at reinforcing slipway facilities to cope with hefty submarine tonnage. In January 1942, the 10^th U-Flotille was also formed in the port, placed under the command of Korvettenkapitän Günter Kuhnke. Lorient — soon known as the “Port of the Aces” — became arguably the most famous of the French bases.  The port was distinguished by presence of so many of the highest scoring U-boat commanders — men like Prien, Lemp, Kreschmer, and Bleichrodt — who quickly became household names worldwideThe seven highest scoring boats of the war were stationed here at some point: U48, U99, U103, U123, U124, U107 and U37) Again, the Kriegsmarine provided extensive facilities for commanders and crew to relax between missions, even so far as to create a bierkellar near the golden sands of Carnac beach. For two years, the world held its breath as U-boats battled with Allied convoys in one of the most decisive arenas of the war. It gradually became apparent who the victor was. The staggering statistics of German U-boat losses attest to the dangerous nature of their service and how the tide of war had turned against them. Allied weapons developed a new and deadly efficiency during the war, and a staggering percentage of operational U-boat crews never returned.The bunkers at Lorient were more complex, sprawling to include several different sites. Like at Brest, U-boats were initially serviced in the open beneath netting and tarpaulins, but early air raids threw into sharp focus the doubtful benefits of this practice. In November 1940, Fritz Todt ­— head of the German labour organization to which he lent his name — visited Lorient with then head of the Kriegsmarine,Grossadmiral Raeder, and his deputy, Konteadmiral Dönitz.  The three planned an ambitious project to build three separate submarine bunkers at a place named Keroman. Two huge, arched bunkers (named “Cathedral Bunkers” or Dombunkers) constructed first already functioned as dry docks, capable of handling two U-boats each, but they alone were not sufficient.Work, begun in January 1941, was completed in stages: bunkers Keroman I, II and III were finished in September 1941, December 1941 and January 1943 respectively.

Keroman I measured 120m long by 18.5cm wide, sufficient room for five dry-dock pens (designated K1 to K5) and a slipway for lifting submarines from the water. Keroman II was on dry land immediately behind Keroman I and was fed with submarines raised using the latter’s mechanical slipway. This “dry bunker” measured 138m long by 128m wide with a height of 7m, and held seven pens designated K6 to K12. The final bunker, Keroman III, was 158m long, 186m wide, and 20 metres high.  Keroman III had two repair pens, each capable of accepting two boats side by side (in four sub-pens designated K13 to K16), and five mooring docks (K17 to K24) again capable of handling two boats apiece. These remarkable facilities enabled a swift transfer of vessels between water and repair yard — the time taken to lift a boat on its cradle from the sea and transfer it to the farthest pen a mere one hour. Imposing steel doors three feet thick could be swung closed across each pen, and two ships were moored in Port Louis Bay immediatley before the bunkers. These two retired warships — Crapaud and Strasbourg (the ex-German light cruiser SMS Regensburg, a veteran of the Battle of Jutland, taken by France at the end of the First World War) provided further shelter for the pens, and each had tethered to them fat barrage balloons, that drifted lazily in the air above to discourage low-level aircraft attacks. Of course the ever-present anti-torpedo nets lay suspended from their steels buoys almost as a final gesture of impregnability. Further concrete submarine bunkers were established in Saint-Nazaire and Bordeaux, the latter the only French U boat base inland of the coast, positioned as it was along the expansive Gironde River.

Coupled with this major installation was the presence in Lorient of another key element of the U-boat war Konteradmiral Dönitz, Head of the KriegsmarineU-boat arm since 1935, Dönitz lived and worked in a requisitioned chateau positioned near the entry to Lorient’s harbour, which included three separate villas for himself and his staff. Immediatley that France had surrendered Dönitz despatched staff officers to select a site for his headquarters. The Chateau du Ter was an inspired choice standing on the Western side of Le Ter River at Kerneval and facing the foreshore of Keroman with its precious submarine facilities. Here, as Befehlshaber der Unterseeboote (BdU, or, Commander-in-Chief U-boats), he ran the wolf packs that nearly strangled England’s Atlantic lifeline (Dönitz was forced against his will by his superior Raeder to move from there to Paris in May 1942, after the successful British commando raid on the port of Saint-NazaireWith British commandoes becoming bolder in their attacks, often as intent on capturing Germans for intelligence reasons as destroying installations, there was real fear that Dönitz would be a target for such a raid). The Kerneval nerve centre — christened “Berlin” by those within — became a veritable fortress with underground bunkers, artillery and machine-gun emplacements, an anti-tank ditch and continually increasing anti-aircraft installations. Indeed the first RAF bombs fell on Lorient’s Scorff River installations on 2nd September 1940.

Eventually men of both the 2nd and 10th U-Flotillas would be accomodated outside of Lorient in special camps, the main site being known as Lager Lemp.