The Invulnerable Nazi Saint-Nazaire Submarine Base

The Saint-Nazaire submarine base is a large, fortified submarine base constructed by the Germans in the occupied city of Saint-Nazaire on the west coast of France.

Prior to the invasion of France, the site was the docks and buildings of the Compagnie Générale Transatlantique (typically known overseas as the French Line), a shipping company famed for its luxury ocean liners.

After the Battle of France, the Germans instigated Organisation Todt (Oberbauleitung Süd), a civil and military engineering organisation to construct a series of large-scale engineering projects in Germany and occupied territories to assist the war effort.

The harbour at Saint-Nazaire was identified for the construction of a large submarine base to service and re-arm U-Boats (Unterseeboots), in their campaign to sink allied shipping and naval vessels during the Battle of the Atlantic.

- Advertisement -
Image Credit : Demeester – CC BY-SA 3.0

Construction began in February 1941 involving 4600 workers who built 14 docks using 480,000 cubic meters of concrete. The base was intended to be invulnerable to allied bombing and was shielded with an 8-metre-thick roof comprising of granite and reinforced concrete capable of resisting event the ‘Tall Boy’ and ‘Grand Slam’ bombs.

The base was also equipped with 62 workshops, 97 magazines, 150 offices, 92 dormitories for submarine crews, 20 pumps, 4 kitchens, 2 bakeries, two electrical plants, one restaurant and a hospital.

On 30 June 1941, Vizeadmiral Karl Dönitz formally opened the U-boat pen, with U-203 (a Type VIIC submarine) being the first boat to occupy one of the pens.

In 1942, an adjacent dry dock near the pens was targeted in Operation Chariot, an amphibious attack in which British commandos rammed an explosive-filled destroyer into the dock to force large German vessels to resort to running the gauntlet through the Home Fleet of the Royal Navy via the English Channel or the North Sea.

The Saint-Nazaire Submarine Base withstood 50 separate bombing raids, resulting in allied bombing targeting the surrounding town and facilities in an attempt to disrupt operations, only finally surrendering on the 10th May 1945 near the very end of WW2.

Header Image Credit : Jean-Pierre Dalbéra – CC BY 2.0

- Advertisement -
Mark Milligan
Mark Milligan
Mark Milligan is multi-award-winning journalist and the Managing Editor at HeritageDaily. His background is in archaeology and computer science, having written over 7,500 articles across several online publications. Mark is a member of the Association of British Science Writers (ABSW), the World Federation of Science Journalists, and in 2023 was the recipient of the British Citizen Award for Education, the BCA Medal of Honour, and the UK Prime Minister's Points of Light Award.

Mobile Application


Related Articles

Study uses satellite imagery to identify over 1,000 Andean hillforts

A new study, published in the journal Antiquity, uses satellite imagery to survey hillforts known as pukaras in the Andean highlands.

Roman defensive spikes unveiled at the Leibniz Centre for Archaeology

In 2023, archaeologists from Goethe-Universität Frankfurt am Main uncovered a series of wooden defensive spikes during excavations of a 1st century AD Roman fort in Bad Ems, western Germany.

Obsidian blade linked to Coronado’s expedition to find the fabled city of gold

Archaeologists suggest that a flaked-stone obsidian blade could be linked to the expedition led by Francisco Vasquez de Coronado to search for the fabled city of gold.

Clay seal stamp from First Temple period found in Jerusalem

Archaeologists have discovered a clay seal stamp from the First Temple period during excavations in the Western Wall Plaza, Jerusalem.

Offering of human sacrifices found at Pozo de Ibarra

Archaeologists from the National Institute of Anthropology and History (INAH) have uncovered an offering of human sacrifices at the Mexican town of Pozo de Ibarra.

Excavation uncovers preserved wooden cellar from Roman period

Archaeologists from the Frankfurt Archaeological Museum have uncovered a well-preserved wooden celler in Frankfurt, Germany.

Preserved temples from the Badami Chalukya era found in India

Archaeologists from the Public Research Institute of History, Archaeology, and Heritage (PRIHAH) have announced the discovery of two temples dating from the Badami Chalukya era.

Excavation of medieval shipbuilders reveals a Roman head of Mercury

Excavations of a medieval shipbuilders has led to the discovery of a Roman settlement and a Roman head of Mercury.