{"id":43705,"date":"2022-09-09T09:44:55","date_gmt":"2022-09-09T08:44:55","guid":{"rendered":"https:\/\/ourtour.co.uk\/home\/?p=43705"},"modified":"2026-04-13T15:09:11","modified_gmt":"2026-04-13T14:09:11","slug":"port-louis-and-the-u-boat-pens-of-lorient","status":"publish","type":"post","link":"https:\/\/ourtour.co.uk\/home\/port-louis-and-the-u-boat-pens-of-lorient\/","title":{"rendered":"Port-Louis and the U-Boat Pens of Lorient"},"content":{"rendered":"\n

“Diwel Didrouz Maro Pa Denn”<\/em>, Breton for “Invisible and Silent, I Carry Death”. Motto of the French Atlantic Submarine Squadron, based at Lorient from 1945 to 1995.<\/p>\n\n\n\n

We’ve just gotten back from visiting the mind-boggling World War 2 U-boat pens at Lorient. While there we spotted a number of motorhomes parked among the complex of enormous concrete structures, and on park4night.com we can see freebie overnighting is allowed. Although it’s not the most salubrious of locations, that’s not the reason we’re not parked there. We weren’t even aware there were U-boat pens at Lorient when we arrived! I know, I know, we really should do more research… <\/p>\n\n\n\n

\"Free<\/a>
Free overnight motorhome parking outside the submarine pens at Lorient<\/figcaption><\/figure>\n\n\n\n

But hey, it’s worked out well enough. Instead we’re staying in one of the three aires at Port-Loius on the other side of the bay (N<\/a>47.706138, W3.355783<\/a>). We’re surrounded by the citadel’s 20-foot high stone walls, which are doing a magnificent job of shielding us from the half-gales which would otherwise have us rocking about like a stick on a spring. It’s one of the Pass-Etapes Camping-Car Park locations and at \u20ac12 a night with electricity it’s a great spot. It’s a campsite in summer, and the shower block closes in the autumn making it an aire (you need a self-contained van). If you’re in a van over 7m, you might want to pick the aire next door in the ramparts, it has easier access. <\/p>\n\n\n\n

\"It's<\/a>
It’s one way in-one way out at this Camping-Car Park aire, and there are a few barrier queues in the morning!<\/figcaption><\/figure>\n\n\n\n
\"Not<\/a>
Not a bad motorhome aire though eh!? Ju took this from the defensive sea wall at Port-Louis, the other side is beach<\/figcaption><\/figure>\n\n\n\n
\"Beach<\/a>
Beach and citadel at Port-Louis<\/figcaption><\/figure>\n\n\n\n
\"he<\/a>
The Port-Louis citadel was used by the Nazis as an interrogation centre in WW2. A mass grave with 69 bodies was found after the war. No-one responsible was ever brought to justice.<\/figcaption><\/figure>\n\n\n\n
\"The<\/a>
The Port-Louis Citadel, a museum today.<\/figcaption><\/figure>\n\n\n\n

A short walk through the town brings you to a ferry which speeds 2km across the huge harbour mouth to the Lorient fishing port. From there it’s about a 1 mile walk through an industrial area to the U-boat pens (there may be a boat direct to La Base<\/em> where the pens are, but we just hopped on the first one going to Lorient). Less convenient than driving to the pens, but more fun, and cheap too at \u20ac1.50 each. The boat granted us a cracking view of the sea-level pens.<\/p>\n\n\n\n

\"A<\/a>
A ferry heading across the front of the U-boat pens at Lorient<\/figcaption><\/figure>\n\n\n\n
\"The<\/a>
The view from the ferry cabin as you’re brought over the water to the Port de P\u00eache ferry terminal<\/figcaption><\/figure>\n\n\n\n

As the Allies fought their way across France and eventually into Germany in 1944 and 1945, the German defenders held onto a ‘pocket’ of Brittany including Lorient and its U-boat pens. They only surrendered here two days after the official surrender in 1945. As they moved in, the French navy found the U-boat facilities to be in good, useful condition and decided to operate their own subs from here, not leaving until 1995. After that the city decided to open it up for a combination of industrial use, as a marina for racing yachts and as a museum for the public.<\/p>\n\n\n\n

\"The<\/a>
The French named the base after Jacques Stosskopf, deputy director during the war who fed information to the Allies. He was denounced under torture by another member of the resistance, deported to a camp in Alsace and executed just before the Allies arrived.<\/figcaption><\/figure>\n\n\n\n
\"Lorima<\/a>
Lorima logos on giant doors of the Keroman 1 sub pen entrances at Lorient. They make carbon masts for very expensive yachts<\/figcaption><\/figure>\n\n\n\n
\"A<\/a>
A yacht leaving Lorient harbour with the U-boat pens in the background<\/figcaption><\/figure>\n\n\n\n

The pens, like those at Saint-Nazaire to the south, are famous. I really should have known they were here, but it’s always more exciting when you arrive without expectations to discover something dramatic. <\/p>\n\n\n\n

I use the words ‘exciting’ and ‘dramatic’ with caution. I’ve had the fortunate to visit a few World War I and II ‘locations’ across Europe and North Africa. Fortifications, resistance bases, museums, concentration camps and places of massacre. They’re all historically interesting to me, but all carry a weight of sadness behind the drama and intrigue. A lot of men, women and children suffered as a result of their existence, it’s not something we forget.<\/p>\n\n\n\n

For me, that motto at the start captures the essence of submarine warfare. Their job was to quietly and without warning destroy ships (and by extension their crews). It was all a giant attempt to deny Britain and later the Soviet Union resources mostly from North America. For six years the Battle of the Atlantic raged across an enormous theatre of naval warfare, and ultimately the submarines failed. <\/p>\n\n\n\n

\"Allied<\/a>
Allied tanker Dixie Arrow, torpedoed by U-71 in 1942 (source: Wikipedia<\/a>)<\/figcaption><\/figure>\n\n\n\n

To sailors everywhere, the U-boats must have been a terrifying prospect. I can’t imagine the bravery needed to head out into the inky blackness of the Atlantic, with no idea what lay beneath hunting you. That said, as the war went on the odds shifted in favour of the convoys and out of the 1162 U-boats built, around half were sunk at sea. You’ve only got to watch Das Boot<\/em> to get an idea of the boredom and terror involved for those lads inside the metal tube.<\/p>\n\n\n\n

Right from the fall of France, Lorient was used as a base for German subs. Initially an inlet on the fishermen’s wharf was built, which allowed the U-boats to be lifted from the water and installed in one of twelve bays via a turntable. From here they could be repaired and refitted. Later a couple of wet docks were built, along with two Dom<\/em> bunkers to offer some protection from air raids, so named as they resembled cathedrals. We spotted these as we walked the circular road around what would have been the turntable. They’re used by various businesses now, inaccessible as far as we could see.<\/p>\n\n\n\n

\"A<\/a>
A Dom bunker (we think!) at Lorient <\/figcaption><\/figure>\n\n\n\n

The soft ground and silting around this part of the port led the Germans to pick a rockier area to extend the base, the Keroman Peninsular. And boy did it need to be rocky, what they built there almost defies belief. A simply enormous amount of concrete and steel was poured into bomb-proof walls, ceilings, up to 10m thick in places. The blast doors, which are still there, frozen in places these days, are a couple of feet thick. They’re a fascinating but architecturally ugly sight from the sea. <\/p>\n\n\n\n

\"Keroman<\/a>
Keroman 3 submarine pens at Lorient. A pretty brutal structure<\/figcaption><\/figure>\n\n\n\n
\"Blast<\/a>
Blast doors in the side of one of the Keroman sub pens at Lorient<\/figcaption><\/figure>\n\n\n\n

Close up, stood touching the walls where you can see the marks of the shuttering planks and rusting rebar, they’re staggering. The only thing I’ve seen quite as concrete-bonkers are the Wolf’s Lair in Poland<\/a> and the Blockhaus d’\u00c9perlecques, a V2 rocket construction site in the north of France. The Allies had a couple of bombs potentially capable of destroying such fortifications: earthquake bombs they called them, the whopping Tallboy and even more monstrous Grand Slam. To defend against these the Germans built double roofs, with a high gap between them. <\/p>\n\n\n\n

An on-target earthquake bomb would blow an almighty hole in the top half (what a noise that must have been), but the second roof and the subs beneath would remain untouched. The German design must have worked, as the Allies decided the only way to successfully attack the pens was to blow up the entire city of Lorient. That way no supplies such as torpedoes could be brought to the subs. This they did, in a series of devastating fire-bombing raids in the winter of 1943, leveling an amazing 90% of the city.<\/p>\n\n\n\n

\"A<\/a>
A Grand Slam 10 ton bomb attack on a sub pen at Valentin (which had much less concrete than the Lorient pens). Source: Wikipedia<\/a><\/figcaption><\/figure>\n\n\n\n

Both the Blockhaus and the sub pens were built by the German Todt Organisation. Here in Lorient they employed 15,000 workers. Half were French, employed by French companies, and the other half were from across occupied Europe and North Africa, housed in camps. They built three sets of protective submarine pens, named K1, K2 and K3. The first two required boats to be lifted from the water, carried to the relevant pen on rails and slid under the concrete casing ready for work. <\/p>\n\n\n\n

The last one, K3, had pens at sea level, so boats could sail in and out quickly, although two of the pens were dry docks so could be used for longer repairs. A fourth building, K4, was started but never finished. It was due to hold a larger class of newer subs, but the need to build the Atlantic Wall drew away resources and all that stands now is a mega-wall of concrete.<\/p>\n\n\n\n

\"Hiding<\/a>
Hiding from the rain in the shelter of K1, opposite the wall of Lorient sub pen building K4, the only part ever completed, in the distance K3<\/figcaption><\/figure>\n\n\n\n

Before heading over on the ferry we’d done some research on how to visit the area (I know, shock, horror!). It wasn’t entirely obvious what was going on, but it turns out there are three museums you can visit:<\/p>\n\n\n\n