BETASOM Submarine Base

Bordeaux, France

BETASOM (an Italian language acronym of Bordeaux Sommergibile) was a submarine base established at Bordeaux, France by the Italian Regia Marina Italiana during World War II. From this base, Italian submarines participated in the Battle of the Atlantic from 1940 to 1943 as part of the Axis anti-shipping campaign against the Allies.

Axis naval co-operation started after the signing of the Pact of Steel in June 1939 with meetings in Friedrichshafen, Germany, and an agreement to exchange technical information. After the Italian entry into the war and the Fall of France, the Italian Royal Navy established a submarine base at Bordeaux, which was within the German occupation zone. The Italians were allocated a sector of the Atlantic south of Lisbon to patrol. The base was opened in August 1940, and in 1941 the captured French passenger ship De Grasse was used as a depot ship before being returned to the Vichy French Government in June 1942. About 1,600 men were based at BETASOM.

The base could house up to thirty submarines, and it had dry docks and two basins connected by locks. Shore barracks accommodated a security guard of 250 men of the San Marco Regiment.

The base was bombed by the British on several occasions, especially in 1940 and 1941, but no significant damage was suffered, except for the sinking of the barracks ship Usaramo. The base was indirectly attacked by Operation Josephine B in June 1941, a raid to destroy the electricity substation that served the base.

The last two remaining U-boats left Bordeaux in August 1944, three days before the Allies occupied the base on 25 August. The last remaining German naval personnel attempted to march back to Germany but were captured by US forces on 11 September 1944.

The submarine pens have proved to be infeasible to demolish due to their massive reinforced construction which had been designed to withstand aerial bombardment. In 2010, after conversion several years previously, approximately 12,000 m2 of the 42,000 m2 building were opened to the public as a cultural centre for the performing arts, exhibitions, and evening events.



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    Founded: 1940

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    4.2/5 (based on Google user reviews)

    User Reviews

    Patrick Dirksen (4 months ago)
    The Naval Base forms the perfect decor for the modern and digital exhibition of impressionist works from Monet, Renoir and Chagal. Accompanied by theatrical music it is an awesome experience. Definitely recommend!!
    sj (4 months ago)
    How does a building this horrible get five stars? The inside and some creative lighting.
    Holly Thomas (4 months ago)
    Such a fantastic and immersive experience, I went with my parents and grandparents and they all loved it!!!
    Ezana ABATE (4 months ago)
    A very unique place that's a must for a visitor.
    Walcz Barnabás (5 months ago)
    Beautiful piece of history. A landmark worth checking out. Acoustics is incredible.
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