Near to Flakturm VI G in Wilhelmsburg, Hamburg, in the surrounding park used to be a bunker on the location of what is now a playground. In 2011 it was fenced in and in decay. It’s purpose remains unknown to us, but it seems to have been either a facility or a barracks of some sort. Maybe the building had something to do with the construction of the Flakturm.
As said, the bunker has been demolished and can’t be visited anymore. Any information on this bunker is appreciated.