Greatstone Sound Mirrors - oddball interwar defence technology
The remnants of a fascinating technological dead end can be seen near Dungeness in Kent. The Greatstone sound mirrors are three concrete “listening ears” built between 1928 and 1935 as part of Britain's national defence strategy.
The idea was to reflect the sound of distant enemy aircraft crossing the English Channel onto a focal point where it could be detected.
The low lying Romney Marsh was well suited for the placement of these three different constructions, which range in size from 20 to 200 feet.
There are several other examples of these early warning acoustic mirrors on the southern and northeastern coastline of England, dating from the early days of aerial warfare. As aeroplanes became faster, the mirrors became less useful, until the discovery of radar rendered them obsolete.
The Greatstone sound mirrors can be visited through open days run by the RSPB. Alternatively, an excellent view of them is possible by the swing bridge, even when access is closed to the public.
Further reading
Links to external websites are not maintained by Bite Sized Britain. They are provided to give users access to additional information. Bite Sized Britain is not responsible for the content of these external websites.