U-boat bases

Hamburg, Germany

The U-Boat bunker "Elbe II"

Plans for the "Elbe II" base in Hamburg were drawn up in 1940. In December 1940 groundwork began at the "Vulkanhöft" area in Tollerort. In March 1941 the foundations were completed: 2,500 38 x 35cm piles, each bearing a load of 60 tons. With 50.000 m3 of concrete walls and ceilings were completed in December 1941. Two boxes covered an area of 112,5 x 22,5 m. work boxes and two cranes were installed within. Hanging steel gates protected the entrance.

Because of the increasing intensity of air-raids, "Elbe II" was used for fitting out boats, new ones and those having happily returned. Two shifts were covered by 200 yard-workers, mostly Germans.


Inside the Elbe II bunker in 1996. Photo by Carl.

The last boats to enter "Elbe II" were also the most modern ones in the world - the type XXI-boats U-2505, U-3004 and U-3506 which had an estimated dive-depth of 400 m. They had to undergo last works before setting to sea with the planned destination of Caribbean. U-2505 had already suffered bomb damage during an air-raid before, and also U-3004 suffered from a mishap during a test-dive. Most of the crew members left between April 15th and 17th 1945 to fight, far away from the sea, against British troops in the Lueneburger Heide, not too far away. Remaining crew prepared the self-destruction of the boats in the beginning of May. Meanwhile, the bunker-gates had already been destroyed during an air-raid on April 8th, and several hits had damaged the roof. In the evening of May 2nd the boats were filled with explosives like dynamite and depth charges.

A fourth boat, the XXI-type U-2501, was lying with only its bow inside the shelter, as did the half completed VIIC boat U-684. The last boat to be sunk was U-2501 on May 3rd 1945. The screw-less training boat broke in two close to the place where it had been built just one year ago at Blohm & Voss.


Inside the Elbe II bunker in 1996. Photo by Carl.

On November 11th 1945, "Elbe II" was blown up by the Royal Engineers, the mid-wall and the roof crashed down and shattered U 3506. The other boats were hardly damaged, U 3004 was at least righted up by this after it had developed a list before. 1949 first salvage attempts commenced. About Easter 1950 this was intensified by the firm H. Fluegge. The divers came to the conclusion that it was impossible to raise the trapped boats on the whole, so the tower of U 3004 was dismantled and an air-pressure-lock installed. The pressure made the rooms of the boat mostly water-free, the holes in the hull were temporarily patched. Now the accu-cells could be removed one after the other, they were well paid then. Fearing a change in the boat's position when finally the hull should also be dismantled, causing perhaps the whole roof crashing finally down, most employees quitted salvage-work after 14 months.

U-2501 was pulled out of the ruin during the 50s and scrapped, the sterns of U-2505 and U-3004 were blown off and also scrapped.

Read about the 3 type XXI boat in the Elbe II


The roof of the Elbe II bunker before being being turned into a car park. Photo by Tim.

There were rumours about a fourth boat traced in 1975, but this was never really confirmed. Since then only souvenir-hunters worked on the ghost-like, but remarkably well kept wrecks in their dark tombs, which became flooded with each tide and reappeared making strange sounds with the falling water all some hours, day after day. In July 1993 it was decided to fill up the west-box with sand, and so was done with seven ship-loads from October 6th to 8th 1995. On October 7th only the periscope stumps could be seen rising out of the sand, but then also disappeared. Today it would be a rather hard digger-job to trace the boats under meters of sand fill.

There was also some demolition work on the East-box from March 1964 lasting about one year during which parts of the side-wall and the roof were cut down and removed. Then the works were stopped due to the immense costs. And so any other proposal how to deal with the area fell through for the same reasons since.

Elbe II bunker today
The area is within the freeport of Hamburg but in recent years the whole area has been filled over and the remains of the base and the trapped boats are now beneath a car park.

U-boat bunker Fink II

Another base in Hamburg was the mostly similarly constructed "Fink II", built from 1940 to 1942 with an overall length of 139 m and a width of 153 m, containing five boxes of 22,5 m width each after the final completion. Fink II was built on existing land and then dug out from there, and the Ruesch-Canal which led to the basin was widened. The fifth box was not constructed until April 1944, and as it was added after the rest was completed, it had to rest on the roof of box 4 and thus was higher than the rest.

130.000m3 concrete were used and 105.000 m3 earth excavated. There was space for 15 U-boats of types VII, IX and XXI, so it was the largest base in Germany (the never completed, larger "Valentin" in Bremen-Farge was only a shipyard). The total weight was 263.000 tons.

The first air-raid on Fink II was on April 4th 1945, but it proved to be a total failure with not a single hit. An attack with two Grand Slams and 15 Tallboys five days later also caused rather minor damage though two VIIC boats were damaged by splinters and one floating dock sunk with U-677 and U-982 in box 5. Some walls settled or moved up to 45 cm. But also 15 civilians having sought shelter in the base were killed, 77 injured.

On October 17th 1945 Fink II was blown up with 30,3 t explosives, including 300 bombs. The roof crashed down, and the walls were partially cut off. Towards the end of the 40s some demolition work was started, but it was not until October 1956 that the complete removal of Fink II began. Today there are no remains of the base, the whole area was filled up again with sand from the river Elbe.

Fink II bunker today
In 2007 the incredibly intact Fink II bunker was rediscovered and landscaped when extending a runway for Airbus. See our gallery of the Fink II base today.

Text on bunkers prepared by Tim Schwabedissen

U-boat bases