page_title: Submarine pen
section_title: St-Nazaire
hierarchical_section_title: Submarine pen / Locations / France / St-Nazaire
caption_attribution_description: Français&#160;: toiture de la base sous marine de Saint Nazaire
context_page_description: A submarine pen is a type of submarine base that acts as a bunker to protect submarines from air attack. The term is generally applied to submarine bases constructed during World War II, particularly in Germany and its occupied countries, which were also known as U-boat pens.
context_section_description: The construction of the Saint-Nazaire submarine base was commenced in 1941, including a bunkered lock. (Elsewhere in the reference, it states that "the excavations" for the bunkered lock were begun in October 1942).
  47°16′33″N 02°12′09″W
  The pens were not affected by the British commando raid in March 1942, whose main objective were the Normandie dock gates.
caption: Roof of the U-boat base in Saint Nazaire.
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