Thoughts on visits: Sound Mirrors near Dover

Apologies first, have been lazy, and not blogged earlier in the day.

Yesterday I came across a postcard among our stock of birthday cards, an upcoming birthday prompted the search. The card, shown below, is of South Foreland Lighthouse and the coast towards Dover. As thoughts of what we’ll do when the country gets back to normal, one thought crossed my mind when looking at the card, we must re-visit the Sound Mirrors at Fan Bay, which I didn’t get enough time to study when we were on our National Trust tour of WWII tunnels and sound mirrors at Fan Bay. The dip in the coastline in the centre of the photo is Fan Bay, where the mirrors are located.

You can read about our visit in 2019 HERE – amazing isn’t it that a whole year has gone by with hardly a mini-adventure or holiday. Here’s to vaccination and 2021. I’ve posted a photo of one of the mirrors at Fan Bay, and a diagram of their location.

Seeing what’s been hidden for over 40 years

At the beginning of July I wrote about our taking a mini-adventure to the Isle of Thanet and hopefully to see some sound mirrors up close.

How lucky we were, the weather was fine, and we saw much that was new to us. We based ourselves in Ramsgate, which has a busy little harbour, plenty of eateries, and has attractive regency and Victorian buildings that have so often been demollished elsewhere in the country.

One of the main items on our agenda was to visit the recently uncovered first World War sound mirrors on the White Cliffs near Dover.

Built as aircraft and airship early warning devices for coastal towns between 1915 and 1930, parabolic sound mirrors concentrate sound waves enabling detection of incoming enemy aircraft. They were developed from sound ranging experiments during WW1 to fix the postion of enemy gun batteries by plotting the sound of gunfire.  Many of the 20 or so sound mirrors survive being located in quiet and out-of-the-way places. They became redundant as the speed of aircraft increased such that the amount of early warning time became so small as to be of little benefit, and the arrival of the more efficient radar.

Two sound mirrors at Fan Bay near Dover were covered up by Kent County Council in 1970’s along with all evidence of adjacent three coastal gun batteries to rid the coast of unsightly redundant wartime buildings and tunnels. In 2012 the National Trust acquired a stretch of the White Cliffs coast and knowing that gun emplacement, searchights and tunnels existed at Fan Bay decided to open them as a tourist attraction. These are the photos of our visit to the Fan Bay Deep Shelter and Sound Mirrors. [More info about sound mirrors can be found HERE, and HERE and HERE].


Off for a mini adventure to, hopefully, see WW2 tunnels and Sound Mirrors

Do you remember reading about [see HERE to re-read] our visit to an industrial history conference in Kent, when I cajoled my dear wife to join me listening about the discovery of Sound Mirrors on the White Cliffs near Dover. [The photo below is from the coference presentation]

At the conference I bought a book on sound mirrors – Echoes from the Sky by Richard N. Scarth, wowee, it’s 450 pages – which I’ve only dabbled into. You know, looking at the pictures and idle reading a page or two.

My resolve was to visit the recently uncovered sound mirrors on the coat at Fan Bay. Weather is set fair, so we’re off to visit them, and other stuff too.

Details of the Tunnels and Sounds Mirrors at the National Trust website. Looks like the site maybe closed, so will need rethink for our visit.

Sound Mirrors uncovered at Fan Bay near Dover

I mentioned that, last Saturday, we attended the South East Region Industrial Archaeology Conference [SERIAC], held at Dartford Grammar School. I attend Surrey Industrial History Group talks, which is where I learned of the conference.

SERIAC is an annual one-day conference organized by a group of Societies in the southeast of England who have an interest in industrial history and archaeology.

In the conference programme there was one talk I was keen to listen to. It was on the subject of Sound Mirrors, and in particular the recent uncovering of two lost sound mirrors at Fan Bay near Dover.

Sound Mirrors were built between the two world wars as early warning detectors of approaching enemy aircraft from the sound of their engines. The convex mirrors work by concentrating sound waves of the plane’s engine so it could be heard before it was visible.

There are Sound Mirrors on the coast in Kent and a number in Yorkshire, built to give advance warning of approaching enemy airships. The increase in speed of aircraft and the invention of radar rendered them obsolete.

I’ve seen the sound mirrors at Denge in Dungeness from a distance, and have long wanted to learn more about them and to visit some.

Robert Hall’s lecture, in which he briefly described their history, focussed on the uncovering of two lost sound mirrors at Fan Bay, near Dover. Here are a few photos of his slides.

To learn more about these interesting monuments in our landscape, I recommend these web sites,