The military structure located at these coordinates is part of the historic Lorient Submarine Base (Base sous-marine de Lorient) in Brittany, France. Constructed under German occupation during World War II, this site was a critical component of the Kriegsmarine's Atlantic operations, specifically designed to service and shelter U-boats. The base, centred on the Keroman peninsula, comprised several massive reinforced concrete bunkers (known as Kerbangs), with the provided coordinates situating it within this fortified complex.
Construction began in 1941 and continued until 1943, resulting in some of the largest and most robust submarine pens of the war. These structures were engineered to withstand Allied air attacks, featuring roofs several meters thick and integrated repair facilities, workshops, and ammunition stores. The base's strategic location on the French Atlantic coast allowed German submarines direct access to the hunting grounds of the North Atlantic, making it a primary target for Allied bombing campaigns throughout the conflict.
Today, significant portions of the Lorient U-boat bunker complex remain intact and are accessible to the public. The site serves as a powerful historical monument to the Atlantic Wall fortifications and the naval warfare of WWII. Visitors can explore the cavernous interiors, view preserved equipment, and understand the scale of German military engineering in occupied France. The base's preservation offers a stark, immersive insight into 20th-century military history and the urbex (urban exploration) appeal of such formidable fortifications.