![P1190586 Hackenberg fortification, 1929-1935. Hackenberg was part of Ligne Maginot, a series of fortified sites between Luxembourg and the Mediterranean sea built to...](thumbs/P1190586.webp)
Hackenberg fortification, 1929-1935. Hackenberg was part of Ligne Maginot, a series of fortified sites between Luxembourg and the Mediterranean sea built to…
![P1190588 The fortification was used in 1940 during the German invasion of France and was not defeated, however, upon the French capitulation, the fortification was...](thumbs/P1190588.webp)
The fortification was used in 1940 during the German invasion of France and was not defeated, however, upon the French capitulation, the fortification was…
![P1190589 The fortification was similar to a submarine: it could be used for several months without any physical contact from outside. Airtight gates and filters were set...](thumbs/P1190589.webp)
The fortification was similar to a submarine: it could be used for several months without any physical contact from outside. Airtight gates and filters were set…