Technical Breakthroughs Of Kent



A distinctive landmark on the White Cliffs of Dover, this historic building was the site of Faradays work in pioneering the use of electricity in lighthouses, and was the first to display an electrically powered signal. South Foreland was also used by Marconi for his successful wireless telegraphy experiments.


Whats new in 2003

Original 3,500-watt lamp on display. Leaflets on local walks




Airship Valley

Tony Banner from Orpington in Kent occasionally visits Godmersham Park Estate near Ashford. There, very much off the beaten track, he has come across a dip in the ground known as Airship Valley and wants to know why it was so named. Making History consulted Ces Mowthorpe, writer on First World War airships, and Greg Ellis of Sunley Farms.


Airship Valley is so named because it was a World War I mooring-out sub-station for British airships, which at the time were operated by the Royal Naval Air Service. The particular model based here was the SSZ or Zero class, which was developed at Capel. The SSZ airships moored at Godmersham  there may have been two or three there  were a development of the Sea Scout airship which met Lord Fishers specification for an airship with a speed of 50 mph, carrying two crew and a wireless operator and with 160 lb of bombs.


The airships were about 112 feet long (far smaller than the German Zeppelins), travelled at about 53 mph and could stay up for ten hours. Godmersham was an excellent location for airships. Even at 50-odd miles an hour it took only a matter of minutes for them to get to the Thames Estuary or to the shipping lanes of the English Channel to the south and east. By the beginning of 1918 the Royal Naval Air Service had airships along the length of the east coast, around to Cornwall and right up to North Wales. Their task was to keep German U-boats away from Allied shipping. Their function was to keep enemy submarines submerged, which would slow them down to a speed of about 5 knots. The wireless operator also had a machine-gun in his cockpit for detonating floating mines.


The site at Airship Valley, which is on private land, is a natural amphitheatre and has an overgrown pit. The gondola of the airship would nestle into the pit so that it would not be blown away by the wind.


During World War I there were twelve RNAS Airship Stations  at Longside (Angus), East Fortune (East Lothian), Howden (Yorkshire), Cranwell (Lincolnshire), Pulham (Norfolk), Kingsnorth (Kent), Capel (Kent), Polegate (Sussex), Mullion (Cornwall), Pembroke (Pembrokeshire), Anglesey, and Luce Bay (Wigtownshire). In addition there were fifteen RNAS Airship sub-stations and mooring-out sites of which Godmersham was one.



After the Battle of Britain had abated the bombing of the South Coast began the Luftwafe making bombing raids on Dover and it's harbour night and day. They not only crossed directly over from France, they also made sweeping raids along the coast bombing and hitting Dover with cannon fire, they also targeted Air fields such as Hawkinge, Manston and Biggin Hill. The Luftwafe crossed the channel with as many as 300 planes in formation the sky was blackened by Luftwafe bombers and the town of Dover would go dark.


As the bombing continued a new threat came from the French coast towards the end of 1940 the German Army started installing their huge guns on the French coast that could fire shells across the channel, the first was the 38cm gun at SIEGFRIED BATTERY just south of Cape-Gris-Nez, followed by Three 30.5 cm guns at FRIED AUGUST BATTERY north of Boulogne, Four 28 cm guns at GROSSER KURFURST at Cape-Gris-Nez, Two 21 cm guns at PRINZ HEINRICH BATTERY just outside Calais, Two 21 cm guns at OLDENBURG BATTERY in Calais, Three 40.6 cm guns at LINDEMANN BATTERY between Calais and Cap-Blanc-Nez, Four 38 cm guns at TODT BATTERY outside Cap-Gris-Nez. These guns were later backed up by three K5 railway mounted guns which were also capable of firing shells not only across the channel but also at allied shipping in the channel At this time the British had little answer to this formidable fire power, a worried Winston Churchill came to Dover to see the situation for himself, he had already ordered the high ground either side of the port of Dover to be heavily fortified with large caliber guns. The only answer this British had to these guns at this time were the Royal Marine Siege Regiment at St Margaret's Bay where they had two 14 inch guns nick named 'Winnie & Pooh' they had been fitted with 18 in turrets to increase the operating room.


These guns were ineffective and slow and could never match the formidable firepower of the German guns. Winnie was the first gun to fire a shell that landed on main land Europe in August 1940, Winnie was joined later in the year by Pooh together they were used to bombard the long range guns on the French coast. These guns were manned by twenty five men of various ranks, there was also a separately manned firing control room, they were protected against Luftwafe low flying air attack by 'Pom-Pom' and 'Ack Ack' anti aircraft crews. Behind the guns were the shell and cordite magazines protected by layers of earth and heavily camouflage, each gun had a railway line running to it for delivery of the shells and cordite.


Winnie and Pooh could not fire on German shipping in the channel as they were to slow and inaccurate, whilst the German K5 railway mounted guns were firing on British shipping in the channel with some degree of accuracy. Winston Churchill was incensed by this situation and ordered the building of new heavy gun batteries in Dover to stop German shipping moving up and down the English channel so freely. Three 6 in guns with a range of 25,000 yards were installed at Fan Bay Battery, Four 9.2 in guns with a range of 31,000 yards at South Foreland Battery, Two 15 in guns with a range of 42,000 yards at Wanstone Battery.


In addition to these guns three railway 13.5 guns were added these were named Gladiator, Sceneshifter, and Piecemaker they were relics of WW1, the first of these to be used was Sceneshifter, when not in use it was hidden from the Luftwafe in Guston railway tunnel hauled there by the Royal Engineers using diesel locomotives.




Early warning sound mirrors


Acoustic Detection Post, Acoustic Mirror, Acoustic Wall, Listening Post, Sound Dish.


An early warning structure built during and after WWI along the south and east coasts of England. Sound detecting acoustic dishes and walls could detect the sound of approaching enemy aircraft at a distance of 8 to 15 miles.


Royal Commission on the Historical Monuments of England

A forerunner of Radar, acoustic mirrors were built on the south and northeast coasts of England between about 1916 and the 1930s. They were intended to provide early warning of incoming enemy aeroplanes and airships about to attack coastal towns. With the development of faster aircraft the sound mirrors became less useful, as an aircraft would be within sight by the time it had been located, and radar finally rendered them obsolete.


Though the sound mirrors at Denge are fairly well known, it is less well known that a number of other mirrors existed, built to a range of different designs. In these pages I have collected some photographs of the surviving mirrors, and some details of where they are if you are interested in visiting them.


The book Echoes from the Sky by Richard N Scarth (published by Hythe Civic Society) gives a detailed history of the sound mirrors and associated research projects, and is essential reading if you are interested in story behind the mirrors.


Mirrors were built in the north east, at


 Hartlepool (demolished)





on the south coast at

 Abbot's Cliff, east of Folkestone

 Denge, Dungeness

 Hythe, Kent

 East of Dover

 Warden Point, Isle of Sheppey


and overseas in



The White Cliffs Underground site has photographs of the ruined mirror at Warden Point on the Isle of Sheppey, the mirror east of Folkestone at Abbot's Cliff, and at Langdon Bay east of Dover, as well as the Lade (Dungeness) mirrors and wall.