Route of the aquatic Maginot line

It was built to establish a natural barrier to the advance of German troops during World War II. The flow of the river "Mutterbach" being too low and irregular, the reservoir ponds (six in number) could supply the channels under all circumstances through a drainage system and flood the area in 36 hours. Today, these ponds have found a beautiful repurposing in fishing and tourism:
- Diefenbach Pond: this is the largest of these ponds in terms of surface area, capacity, and dam height.
- Rémering Marsh Pond: a peaceful valley situated between two forests that, in the early 1930s, would become a military reservoir pond intended to supply the "Venice of the front."
- Hirbach - Holving Pond: remnants of the "Casemate of Remembrance," a dam built on the road, a dike leading from Holving to Hirbach, Hirbach pond, arranged to flood the valley (now an outdoor recreation center in Holving).