The U-boat bases in France were the home port of the most famous U-boat flottillas from 1940 to 1944 :
- Lorient U-boat base : 2nd and 10th flottillas. Built by the Germans between February 1941 and January 1943, the Keroman U-boat base was designed to house thirty U-boats and their crews. Once the war ended, this unique site in the world became the main base of french diesel powered submarines before being finally closed in 1997.
- St-Nazaire U-boat base : The St-Nazaire U-boat base was built between 1941 and 1942 by more than 4600 workers of the "Todt Organization". The construction of the base required more than 313,000 cubic meters of concrete. The bunker could accommodate giant XXI submersible with its 14 cells (8 dry docks).
- La Rochelle U-boat base : La Rochelle was the home base of the 3e U-Flotilla, which officially moved in from Kiel in October 1941. The base is located a few kilometers west of La Rochelle, inside the commercial port of La Pallice.
- Bordeaux U-boat base : 12th flottilla (+ italian submarines). The bulding of the protective bunker started In September 1941, to protect the submarines from the bombings. On october 1942, Bordeaux beacame the home base of the 12th German flotilla and the u-boat bunker became operationnal on january 17, 1943 when the U-178 entered the bunker for refit.
https://www.uboat-bases.com
