This short slide-show depicts my son and I exploring these amazing icons of early long range sound detection, situated on the remote Denge Marsh area of Romney Marsh in Kent.
I must apologize for the shot of my son without his top on, as he got soaking wet, attempting to cross a section of water that cuts off the sound mirrors from the mainland! I also make a reluctant appearance, standing within the concrete dish, so as to show the scale of these things.
Ironically, they were never used in a war time situation, because shortly after they were built and tested, some bright spark ("Heinrich Hertz") invented Radar.