In the photo, you see an ammunition depot. I shot the photo in a forest in Heidekamp, outside of Lübeck but very close to Reinfeld. The bunker is one of twelve ammunition depots in our area that were used by the German federal government until the end of the cold war. The ammunition was stored to be able to blow up bridges of strategic value, to prevent enemy troops to advance if it would have come to an invasion. Today, the bunker has a peaceful use case. The Naturschutzbund Deutschland (NABU), a nature conservation association developed it into a quarter for bats.
The bunkers are suitable because our domestic bats need frost-proof, moist and undisturbed roosting places. Many of our domestic bats prefer underground places. The Naturschutzbund Deutschland arranged 60 hollow building bricks in the bunker for the nocturnal mammals. The bricks are covered with soil, which results in a constant temperature with a humidity of 80%. That is also possible due to a gravel layer that was brought into the bunker as well. The place with the surrounding forests and ponds is an ideal habitat for the bats. There are 15 different bat species in Schleswig-Holstein, but Germany-wide there are 23.