The submarine base of Saint-Nazaire is a large fortified U-boat pen built by Germany during the Second World War. Before the war Saint-Nazaire was one of the largest harbours of the Atlantic coast of France. During the Battle of France, the German Army arrived in Saint-Nazaire, in June 1940. The harbour was immediately used for submarine operations.
In December, a mission of the Organisation Todt inspected the harbour to study the possibilities to build a submarine pen invulnerable to air bombing from England. Work soon began under the supervision of engineer Probst.
The selected space was that of the docks and buildings of the Compagnie Générale Transatlantique, which were razed. Building began in February 1941. The adjacent dry-dock in Saint-Nazaire dock was the target of Operation Chariot, a British commando raid in 1942, the U-boat pens were a secondary target of the raid. The attack successfully disabled the dry-dock by ramming an explosive-filled destroyer into it, and by demolition teams wrecking the pumps and electrical system.
The base was 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 the roof is one completed and one uncompleted M19 Maschinengranatwerfer automatic 5 cm mortar bunker.
The zone of the base was abandoned for a long time. In 1994, the municipality of Saint-Nazaire decided to re-urbanise the base, in a project name Ville-Port. The base now features several museums, including a mockup of a transatlantic liner called the Escal'Atlantic, and the French submarine Espadon.
References:Ehrenbreitstein Fortress was built as the backbone of the regional fortification system, Festung Koblenz, by Prussia between 1817 and 1832 and guarded the middle Rhine region, an area that had been invaded by French troops repeatedly before. The fortress was never attacked.
Early fortifications at the site can be dated back to about 1000 BC. At about AD 1000 Ehrenbert erected a castle. The Archbishops of Trier expanded it with a supporting castle Burg Helferstein and guarded the Holy Tunic in it from 1657 to 1794. Successive Archbishops used the castle's strategic importance to barter between contending powers; thus in 1672 at the outset of war between France and Germany the Archbishop refused requests both from the envoys of Louis XIV and from Brandenburg's Ambassador, Christoph Caspar von Blumenthal, to permit the passage of troops across the Rhine.