This may be of interest to relevant stakeholder organisations and public authorities. This post concerns all structures that we located and documented during our two-day survey in March 2025. In light of part of this defensive line having recently been backfilled, it appears important to share these locations so that authorities can under no circumstances claim lack of knowledge when issuing building permits for development projects.
It should also be clearly stated that many of these structures host significant bat populations. However, visiting these sites is not without risk; many are structurally unstable and at risk of collapse, and without the necessary expertise it is strongly advised not to enter them.
I make my photographs available on this blog free of charge under a Creative Commons (CC BY-SA) licence, so that no one needs to enter these places unnecessarily, thereby avoiding any risk to life.
During our survey, we spoke with several local residents who assisted us in locating various sites. To the north and south of the position, we respected the perimeters around private residences, as it was not possible to obtain permission from every occupant. (it was not possible to determine which parcels belonged to which residents.) We therefore limited our work to the forested areas, conducted with due respect for the local fauna and flora. We also treated the agricultural fields with respect, keeping strictly to the edges as is customary, even if it meant taking a considerable detour on foot.
I would also like to sincerely apologize to any landowners we were unable to locate if this has caused any offence. It is my hyperfocus that drives me to document everything as thoroughly as possible; for me, every stone tells a story and research should be shared!
I would also like to sincerely apologize to any landowners we were unable to locate if this has caused any offence. It is my hyperfocus that drives me to document everything as thoroughly as possible; for me, every stone tells a story and research should be shared!
I would also like to thank Google Earth and the Bundesarchiv, where I was able to retrieve the trench maps that allowed me to create the layering shown below. We are a non-profit organisation, and we therefore use only cost-free software wherever possible.
Legend: blue indicates the trenches, red indicates the underground structures.
