This site I had found during the research for the object of yesterday's post.
These are the remins of a heavy anti-aircraft gun battery that was mainly used as a training facility. Airplanes would fly past the coast, dragging "air bags" behind them that the gun crews had to hit.
There is not much left, almost the entire place has been levelled - wether by allied fire or by British deconstruction after the war - I don't know.
Anyway, the walk to the site through a little forest and across some fields made for a marvellous Sunday afternoon trip!