October 2026
Given Cornwall’s strategic geographical position overlooking the South-Western Approaches it is not too surprising that World War Two saw a number of radar stations sited in the county. I am often asked for information on individual sites but when this summer I was asked for an overview of the radar set up in the county there was little online that I could direct my enquirer towards, so here is a brief summary of the 5 Chain Home Radar Stations, the 10 Chain Home Low Radar Stations and the 4 Chain Home Low Extra Low Radar Stations (Some of the CHL also had CHEL capabilities as time wore on but these four were specific in their provision) and the 2 Ground Control Intercept Stations. These are not to be confused with the myriad of Y stations for army and navy, the Radio Security Service Listening Post at St Erth or the shore to ship wireless stations for the naval and merchant shipping off the 320 miles of Cornish coastline or the ground to air wireless stations for the RAF and later the USAAF. In other words Cornwall was full of aerials (they’ve just been replaced by wind turbines and solar farms today!!) and so there is a fair bit of confusion on a local level and online about just what was what. This article will concentrate on radar and hopefully go a small way to clarifying the situation.
At the time of the Munich Crisis in 1938 Cornwall did not have a military airfield. There had been a couple of grass field sites used in World War One by balloons and fixed wing aircraft such as RNAS Mullion on the Lizard and RNAS Padstow at Crugmeer on the north Cornish coast or RNAS Newlyn which had seaplanes but these had long passed into disuse by the 1930s. There were a couple of small civilian aerodromes such as Land’s End and Trebelsue but these were little more than grass landing fields with a hut. So, when in the RAF Expansion Programme it was decided to site an RAF Fighter Sector Station at St Eval between Newquay and Padstow on the north coast the need for radar provision also grew. As the Chain Home provision began to extend along the south coast of England it was realised that to be effective this needed to extend all the way to the tip of Cornwall.
Once war was declared surveys were carried out on several sites for Chain Home stations in Cornwall along with some Chain Home Low stations which could be brought online at a greater speed with the use of mobile sets in the first instance.
Thus the first Chain Home Radar Station to be established in Cornwall was CH16 RAF Drytree on the Lizard on the 25th November 1940. The first set up was mobile utilising 70ft aerials on vans with a range of 30 miles. Work on the permanent site began in the spring of 1940 with 300ft transmitter towers being erected in a V formation to give coverage south-east towards the approach to Falmouth – a category A port: to be defended at all costs – and south-west across the South Western Approaches. It had a range of 200 miles for high flying aircraft. The site had a Type B Receiver Block between the two receiver masts and later added the IFF system – Identification Friend or Foe – to determine whether approaching aircraft were friendly or hostile. For the technically minded Advance Chain Home was first operational on 25th November 1940, Intermediate Chain Home on 21st March 1941 and Final Chain Home on 12th September 1941. After the army defending the Cornish coastline during the invasion scare of 1940 were withdrawn the Corps of Military Police (Vital Points) and the Coverack Home Guard were detailed to defend the radar station until the RAF Regiment took over its defence on 15th May 1943. Its personnel were billeted in requisitioned houses and hotels across the Lizard from Helston to Coverack. The station closed in 1946. Part of its site was repurposed for the Goonhilly Earth Satellite Station in the 1960s and some of the wartime remains are accessible from the paths round the Nature Reserve which occupies the remainder. Check out my You Tube video on the site: https://www.youtube.com/watch?v=ITa7LyVigL4
The first Chain Home Low Radar Stations established in Cornwall were CHL 15A Rame Head in south east Cornwall overlooking the approaches to Plymouth with its naval dockyard at Devonport and CHL 18A Carnanton near the village of St Mawgan, near Newquay, on 4th June 1940. At Rame Head the gantry was put on the coastal side of the old chapel while the huts were on the landward side, one on the slope down from the chapel and others on the level ground of the dip on the landward side. It is possible to make out their sites even today. The Corps of Military Police (Vital Points) defended the station until 15th May 1943 when the RAF Regiment took over. Later in the war a Chain Home Extra Low Radar Station was established at Rame Chapel in a field the other side of the lane near the parish church. This was known as K167 Rame Chapel. Little is known about the operational details of these two sites and any information would be gratefully received. CHL was first used as a coastal defence radar and so sites were often operated by the army with the RAF taking them over once the threat of invasion had passed.
CHL18A Carnanton was probably the first radar station in Cornwall providing information during the early air raids at the beginning of July 1940 that saw loss of life in Falmouth and the initial skirmishes of the Battle of Britain in the south-west (St Eval’s Spitfires defended everything from the Isles of Scilly to Weymouth!). The station initially reported direct to RAF St Eval until a more comprehensive network was established across the county. The station was closed by mid 1942 in order to make way for the long runway at RAF St Mawgan so virtually nothing remains of this site. Again, because of its brief life, little operational detail is known and any information would be gratefully received.
The desperate need for radar cover increased through the summer of 1940 with the aerial onslaught against the country. In September a number of sites were surveyed for Chain Home Low Radar Stations but not all were developed. One example that wasn’t is M93 CHL Dodman Point which looked at a field above Vault beach. It was rendered superfluous by the development of M92 CHL Polruan and M94 CHL Jacka at Portloe although these didn’t become operational until early 1941.
The next stations to come online in 1940 were CHL16A Pen Olver on the tip of the Lizard, CHL17A Mark’s Castle at Land’s End and CHL18A Trevose Head (taking over Carnanton’s designation) on the north coast near Padstow. Pen Olver was established on 29th October 1940 with Wrens working to report surface ships, WAAFs to report low flying aircraft and the army – 30 Duke of Cornwall’s Light Infantry Regiment - guarding the cliff top site by the Lloyd’s Signal Station until the RAF Regiment took over the defensive role on 15th May 1943. Female personnel were accommodated at the nearby Housel Bay Hotel while the men were billeted in and around Lizard village. Pen Olver was upgraded to Chain Home Extra Low in 1942 when it became known as CHEL K168 Pen Olver. The station achieved a degree of notoriety when in October 1943 its commander F.O. William Croft had an affair with WAAF radar plotter Cpl Joan Lewis. When the pair were to be split up by the RAF they embarked on a suicide pact in the Housel Bay Hotel’s summerhouse and in the early hours of 16th October shots rang out and Lewis was found dead. Croft was tried and found guilty of her murder despite his defence plea of not guilty due to it being a suicide pact that he’d been unable to go through with. The jury were never presented with the evidence regarding a third bullet jammed in the pistol. Full details of this story can be found in my February 2025 blog here: https://www.philhadleypublications.com/post/february-2025 The station received a new wooden tower in 1944 but is thought to have closed in late 1945.
CHL17A Mark’s Castle was established on 16th October 1940. Fifteen year old Sennen lad, Bryan Roberts, an apprentice carpenter at the time, was one of the locals to help build it. RAF electrician, Sgt Reg Stephenson was among those involved in the wiring and cabling. The site was bombed on Saturday 14th June 1941. Of the three bombs dropped, two failed to explode and the third hit the Land’s End Hotel killing one and injuring seventeen. Today bases of some of the buildings remain such as the Operations Block and three huts. There is also the remains of an air raid shelter on the site while traces of the white path edging, prominent in all the wartime photographs and film footage of the site, can still be found. Check out my YouTube videos on the site: https://www.youtube.com/watch?v=XcI8OGM5pu4 and https://www.youtube.com/watch?v=F7kHwSPFnyQ
CHL18A Trevose Head was established on 16th October 1940 operating AMES Type 2 radar. Little operational detail is known of the site but Canadian Ft Lt James Rowlatt, RCAF was its Commanding Officer prior to being posted to Ventnor on the Isle of Wight in 1942. Many of the WAAFs were billeted in Padstow. Today little remains of the site although it is possible to find some concrete remains by the hedge in the corner of the field where the demolished buildings were dumped. Only the generator house still stands used as a shed by the farmer. Check out my YouTube video on the site: https://www.youtube.com/watch?v=QVOXRwEurPo
Next to come online were three more Chain Home Stations which significantly improved the long range coverage from Cornwall. CH15 Downderry was built on the Cornish south coast in the village that gives it its name and was planned as part of the first wave of south coast stations. It was established by mid April 1941. In the early days personnel were billeted in the small village or bussed in from elsewhere. Commanding Officer up until 1942 Sqn Leader Copperwheat arranged for the accommodation camp to be built at Broad Yards. The station was always considered vulnerable due to its position just on top of low cliffs and so there were several AA gun positions above the village and pillboxes covering the beach. The WAAFs stationed there were all taught to shoot as fears of a reprisal raid grew after the successful raid on the German radar site at Bruneval. Little remains of the site today, just a Type C Receiver Block and the power house. My YouTube video shows what remains there were in 2011 https://www.youtube.com/watch?v=aecfmpupgD4 but these have now been turned into living accommodation although the Receiver Block retains some of its character.
CH17 Sennen started in a field at Trevescan when the land was requisitioned in 1940 by the War Department and a mobile radar station was set up. The land belonged to Mr Hicks and was farmed by Mr Hoskin. The radar operators used some of the little farm buildings as their base and lodged in the farm and nearby cottages. Further land was acquired on the Hall’s farm at Skewjack and the neighbouring farms of Trebehor and Trengothal and building continued into 1941. The Operational buildings were dispersed throughout the site while the domestic site was constructed near Skewjack Cottages. Again Bryan Roberts, the 15 year old carpenter’s apprentice from Sennen, was involved in the building. He recalled, “I got a letter in the post telling me to report to Skewjack the following Monday.” There were four 350ft transmitter towers and four 240ft receiving towers. The site also had an IFF cubicle and aerial. Officers lodged in Old Success down in Sennen, RAF and WAAFs were in the Sennen Cove Hotel whose tennis courts were used to erect huts housing domestic quarters and a sick bay. Sennen later operated as part of the GEE navigational system developed by Robert Dippey and was linked to the South West Chain Master at RAF Sharpitor. The site was also developed in the 1950s as part of the ROTOR system used during the Cold War. The site eventually closed on Thursday 26th March 1970 when No 428 Signals Unit RAF Sennen saw the end of the GEE system after 25 years of service when the 10 stations were closed down. The fact of its continued use means that many of the wartime buildings are still standing including an operations block, various bunkers, a picquet post, a nissen hut and mast bases. Be aware most of these are on private farmland although a couple have been developed into residential properties. The domestic site was used as a Surf Village in the 1970s and was demolished in 2000. The Sennen Cove domestic site is today a car park. Today Skewjack houses the British terminal for FLAG – Fibre optic Around the Globe – with two cables from the USA and France terminating here. Check out my YouTube video on the site https://www.youtube.com/watch?v=PJFMe74Y04M
CH18 Trerew was built straddling the Newquay to Redruth road (now the A3075) near Crantock just outside of Newquay. It was established on 18th April 1941. The site had the usual Type C transmitter and receiver blocks with their four 350ft steel transmitter aerials and four 240ft timber receiver towers. There were generator houses, an armoury and some domestic quarters. The main domestic site was down the hill towards Newquay and today is a camp site/holiday park. The station ran its own newssheet called What’s Cookin’ during the war. Trerew was developed for ROTOR in the 1950s and several of the wartime buildings were adapted like the E shaped building which became an administrative centre. Again because of its later use many of the buildings remain although are in poor condition. They are on private farmland. Check out my YouTube video of how things were in 2011 https://www.youtube.com/watch?v=g37ogVaisW8
Then from April to June 1941 came several Chain Home Low Radar Stations filling in the gaps in the coverage around the Cornish coast. CHL M92 Polruan at Blackbottle Rock straddled the coast path overlooking Lantic Bay on the south coast. The operations block was south of the footpath with its antennae on top. A 100ft tower dominated the skyline from the corner of the field. The generator hut was north of the footpath – its generator bed still remains – with a nissen hut next to it. There were then three huts by the barn in the corner of the next field where the stand by set was located. The other side of the lane down to Polruan was a small domestic site. The Americans took over the site in February 1944 and set about re-arranging things. They put in 3 huts by the hedge in the next field to improve the accommodation. When after the war the land became the property of the National Trust, those guardians of our historical heritage decided that an old radar station was a blot on the landscape spoiling the view and so demolished it. However, they did not remove the rubble but merely tossed it down the coastal slope where large parts of it can be found today amidst the undergrowth. Further details on the radar station can be found in my video on Polruan and the East Side from the Bodmin Stop Line series starting at 16m 53s https://youtu.be/R4qXEMR-szo?si=jgCRgHDJ_rzxlUM1&t=1013
CHL M94 Jacka was sited on the cliffs west of Portloe. It was first manned by the Royal Artillery in its Coastal Defence role before the RAF took over. The radar site housed the operations block, a stand-by set, two accommodation blocks, a mess hut and ablutions block. Just up the road at Camels with ten huts including a mess, a cookhouse and motor transport workshop. It housed approximately 50 personnel. Officers were billeted at The Straythe, other ranks at Camels. Once WAAFs were stationed at the radar station they were accommodated at the Nare Hotel at Carne. A few radar operators had private billets in the village of Portloe. As well as CHL the site also saw Types 31 and 52 radar as well as IFF. On 10th March 1944 Jacka began ‘telling’ its plots to Trelanvean instead of Rudloe Manor. The station had an American commanding officer from January to March 1943 when Lt Sanger B Steel was in charge before he was then posted to the Aleutian Islands. The site was defended by 30 Duke of Cornwall’s Light Infantry Regiment until the 15th May 1943 when the RAF Regiment took over.
CHL M100 Trewavas Head was located at Rinsey Head amongst the ruins of the Wheal Trewavas copper mine north of Porthleven. It was commissioned on 12th April 1941 and was primarily sited to detect enemy aircraft flying into Mount’s Bay before sweeping round to fly over the Penryn reservoirs in an attack from the landward side on Falmouth Docks and escaping out over the sea. Trewavas Head could detect aircraft flying at 500ft up to 30 miles away and higher aircraft up to 100 miles away. Accommodation was at the nearby Trewavas Farm and at Rinsey House. The site had closed by 31st December 1942 as the bombing threat had rescinded and other stations improved the coverage across Cornwall. Check out my YouTube video of the site https://www.youtube.com/watch?v=WAsJUHDN-h4
CHL M108 Dunderhole was located on the north coast between Tintagel and Trebarwith and again started life in a Coastal Defence role manned by the army. In 1942 the station was upgraded to Chain Home Extra Low in order to help deal with air attacks on convoys sailing off the north Cornish coast and came under RAF control. As well as the high cliffs the site was defended by barbed wire obstructions and minefields. The cottages that now form the Tintagel Youth Hostel were used to accommodate personnel with other facilities provided in nissen huts on a neighbouring farm. A few concrete bases by the coast path and a nissen hut, along with the Youth Hostel, are all that remain of the site today. Check out my YouTube video of the site https://www.youtube.com/watch?v=hKEQ-zspDrM
CHL M115 Hor Point again started life in a Coastal Defence role built and manned by the army becoming operational in April 1941. Hor Point is on the north coast just over a mile west of St Ives. Little is known about the operational details of this site. However, it had become redundant by late 1944 and its demise in spectacular fashion at the hands of the Commando based in St Ives was filmed as part of a Commando training film. You can see the clip here https://youtu.be/F11UABufuos?si=wpRogT77PK3S6-Bo&t=868 and see the remains in my YouTube video of the site here https://www.youtube.com/watch?v=6dm9J3z2Bz8
1942 saw an expansion of the Chain Home Extra Low radar capabilities in Cornwall using a concentric radar operating at a 10cm wavelength to provide low coverage radar and while several existing stations were upgraded there were also some new ones built. I have already mentioned CHEL K167 Rame Chapel in south-east Cornwall. CHEL K169 Chapel Carn Brea was established in early 1942. It was situated on the first hill in Cornwall overlooking Land’s End and Sennen and should not be confused with Carn Brea between Camborne and Redruth. The operations block was in a hut with a rooftop aerial gantry that was sited near the modern viewfinder on the hill’s summit. There were additional huts on the eastern slope. Accommodation was at local farm billets or in the RAF Sennen Domestic Site down in Sennen Cove. Check out my YouTube video on the site here https://www.youtube.com/watch?v=_8qNn5srVYU
CHEL K181 St Agnes Beacon first saw a Type 57 mobile radar used on the hill that overlooks both RAF Portreath and RAF Perranporth in May/June 1942. It then operated Type 31 radar and then Type 41 from December 1944. The army were involved until 6th October 1943 when the RAF took over. The station also saw a number of Royal Canadian Air Force personnel with one, Albert Soklofske, marrying a local girl in 1945. The properties called Chillys and Mayfield in Beacon Road were requisitioned by the War Department for accommodation for the radar mechanics. Other personnel were billeted throughout the village of St Agnes and outlying farms and hamlets. The site closed on 1st June 1946. A number of hut bases, aerial tower bases and cable stays can be found amidst the heather and gorse on the top and northern slope of the Beacon. Check out my YouTube video of the site from 2011 https://www.youtube.com/watch?v=tYkbJ1AyrnI
Because of the high number of air raids on Falmouth (It had 783 air raid alerts by the end of the war) it was decided to improve the Chain Home coverage with a second radar station to cover the port and the English Channel. Thus work began on CH74 Trelanvean in 1941 – the site was surveyed on 12th January 1941 with the go-ahead given on 1st March 1941 on land owned by Mr Donald Thomas - and it became operational on 17th May 1942. It was sited near the hamlets of Trelan and Zoar near Coverack on the Lizard. It had the usual array of two pairs of taller transmitter towers (325ft) and two pairs of shorter receiver towers. Its technical site was at 20 Acre Plantation while the domestic site was at Trelanvean Farm. Trelanvean was unusual as it was built as a Final Chain Home station; it didn’t go through the usual stages of Advance and Intermediate. IFF arrived on the site in December 1942. The station was operated by approximately 50 RAF personnel, 50 WAAFs and a number of RAF RDF mechanics. The Operations Room on the Kestlemerris site was prone to flooding (not surprising in the moorland peat!) and so two fire engines were kept there to do the daily pumping job. From 10th March 1944 the station acted as a Filter Room to RAF Jacka. Trelanvean was guarded by the Corps of Military Police (Vital Point) until 15th May 1943 when the RAF Regiment took over. The station closed on 25th November 1945. Many parts of the site remain on private farmland and have provoked renewed interest in the 21st century with several archaeological surveys being done.
There was also a radar station at CH? Peninnis Head, St Mary’s, Isles of Scilly, but I have yet to find which type it was (any information gratefully received as it never shows up in any lists online). It was operational by August 1940 as on the 21st of that month it was attacked by the Luftwaffe – the first hostile enemy action on the islands. They returned to bomb it on several occasions and eventually destroyed it in the late summer of 1941. Very little trace of it remains today. As far as I can find out it was never replaced and the islands relied on the GCI station at RAF Newford to plot incoming hostile aircraft. In 1943 IFF was installed at the Woolpack Battery, an abandoned gun emplacement on St Mary’s that had been built in 1898-1901. On this site a homing beacon was erected in 1943 to guide anti-submarine aircraft returning from patrol to airfields in the south-west of the mainland. Two raised concrete mast bases are still there on the gun emplacement aprons. One of the magazine’s cartridge/shell stores was used as barracks for RCAF personnel.
Cornwall was to have two Ground Control Intercept stations where radar operators were able to guide pilots in the air towards their prey. GCI 24G Treleaver was built south east of CH74 nearer Coverack. A mobile system was first installed in June 1941 with two lorries each towing trailers with aerials and operated by RAF men pedalling as if on a bike (making it impossible to operate in high winds – not an uncommon feature of the Lizard peninsula). One lorry was the transmitter with an aerial about 10ft high, the other – the operations room – was the receiver with cathode ray tubes and a plotting table. A third lorry contained accessories and towed a generator trailer. On one side of the Ops Room was the Plan Position Indicator and opposite the electrostatic height tube – screen with split trace. The Controller sat in the middle viewing both screens and by measuring the time difference in the radar bounce from different parts of the aerial and taking the range into account, height could be estimated. Other staff included a WAAF operator at the Navigation Board taking into account winds and cloud height, a Recorder who recorded information on tracing paper over the operational maps, a Telephonist operating the Private Branch Exchange and a Teller who was in contact with RAF Portreath and RAF Predannack. At Christmas 1942 the station received an upgrade to an Intermediate GCI. This brought a wood framed building with an aerial 35ft high which turned in complete circles acting as both transmitter and receiver. To the delight of the pedallers this was power operated! Within a few months a brick and concrete Happidrome was built which provided a range of 45 miles for interception. This 160ft long room, 35ft wide was built partly underground. Four pairs of sets were installed so the station could monitor aircraft on different frequencies which proved very useful in rescue work. One of the station controllers, Margaret Diplock, recalled, “We saw on our new screens a pilot bale out of his plane close to the French coast and we watched the blip on the calibration scale of the height tube slide from 600ft to sea level as the parachute glided down to the water. We were able to guide the Walrus air-sea rescue plane to within one mile of the place. No one wanted to go off watch until the rescue was complete.” WAAF operators were accommodated at the Headland Hotel in Coverack, other personnel at Channel View. The men’s billet was at Bay Hotel with officers at Porthgwara. The radio mechanics were at the Paris Hotel then in the summer of 1944 were moved out to Bell Tents with a marquee for their mess. The site was developed for ROTOR in the 1950s opening in 1954 meaning several of the buildings remain today, most on private farmland. The Cold War Operations Room is now home to Lizard Ales.
The second station was CGI Newford at High Lanes on St Mary’s, the Isles of Scilly. This helped with the aerial battles in the South Western Approaches where the anti-submarine war was keenly fought by both sides. The station recorded guiding intercepts at up to 90 miles if the weather and atmospheric conditions were right. The station was also involved in co-ordinating the rescue of many downed aircraft and had a direct line to the RAF air-sea rescue unit based in St Mary’s harbour as well as the Sector Operations Room at Portreath. Author R.L. Bowley has said in the event of the station being bombed, a mobile unit was placed on the golf course. It is believed the station became operational in 1941 and continued in service until the end of the war. Few details are known and any information would be gratefully received.
A final development was that of OBOE – the first electronically controlled system used to direct bombers onto their target. Cornwall hosted one of the two stations in the south west at RAF Treen which came under the umbrella of RAF Sennen. I have written a blog just about Treen and you can read it here https://www.philhadleypublications.com/post/may-2023
Thus there were a large number of personnel serving at radar stations in Cornwall. During the war their work was top secret but since many have shared their experiences and photographs to help us understand their work and their experiences. We salute their service and remember what they did to help keep Britain free and to win the peace that we have enjoyed for 80 years. If you have any information or photographs relating to Cornish radar stations and their personnel please do get in touch by leaving a comment below.
Until next month, Shalom.
Comments