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Orford Ness: Military secrets and unique wildlife on the remote Suffolk coast

Shingle spit and you'll miss this science and history on t' beach gem

Geek's Guide to Britain An isolated spit of land on the Suffolk coast, so narrow that in places you can cast a stone from one side to the other, seems an unlikely place to find the remnants of nearly a century of advanced scientific military research, but that's exactly what you will discover if you visit Orford Ness.

Take the brief ferry trip across the River Alde to the 3.5 square miles (9km2) Ness, and you will also find a globally significant wildlife reserve and the remnants of one of the United States' greatest military white elephants.

The evolution of Orford Ness from marshy backwater to a central part of Britain's weapons development ability began in 1913 when the War Office purchased part of the Ness to act as a base for the fledgling Royal Flying Corps (RFC).

The site's isolation, surrounding flatness and proximity to the sea were all considered important prerequisites. The first had more to do with the perceived unreliability of contemporary aircraft than anything else. The RFC didn't want its planes falling out of the sky in built-up areas.

In 1915, the Ness became co-host to what was known as the RFC Aeroplane Experimental Research Station, acting as a satellite of the larger RFC aerodrome at Martlesham some 18km (11 miles) away as the B.E.9 flies. This was the start of 60 years of boffinry on Orford Ness.

The research carried out at Orford Ness during the First World War covered a bewildering range, from work on parachutes and aircraft camouflage (the RFC's original dark green varnish was given the acronym NIVON for Night Varnish Orford Ness!); to the suppression of aircraft engine noise; an interrupter gear to match the German innovation; night flying tactics; bomb and machine gun sights; parachute flares; and even the creation of artificial clouds.

Aerial view of the Cobra Mist site.c Creative Commons2

Aerial view of the Cobra Mist site (Click to enlarge). Pic By Hohum, CC 3.0

Reading about these early experiments, it is constantly surprising that accidents were few and far between.

Windy accident

In 1917, while testing a new bombsight, a pilot released the weapon unaware that a strong southerly wind had blown his aircraft over Aldeburgh. Rather than fall harmlessly onto the Ness, the bombs – duds, thankfully – bracketed the nearby Martello tower that housed an Army detachment. The garrison commander demanded the aircrew be arrested.

The site of the original RFC airfield has now been reclaimed by marshland, partly thanks to serious flooding in the mid-1950s and partly due to the work of the National Trust, which now owns most of the Ness, to manage its return to a status more akin to before the military arrived.

From 1918 to 1924, the facilities on the Ness slumbered under a "care and maintenance" order. The pace of life quickened again in 1924 when Orford Ness was reactivated and redesignated as a satellite operation of the Aeroplane and Armaments Experimental Establishment, again based at nearby Martlesham.

Trials conducted during this period included Lethality and Vulnerability tests on RAF aircraft. Essentially this involved blazing away at static aircraft with machine guns – both British and German – to see which bits dropped off. Tests of this nature were carried out on the Ness until 1959.

The Plate Store building – so called because it was used to store target plates of aircraft armour as well as conduct impact experiments – is a reminder of this work.

It is also from this inter-war period that two of the more significant surviving buildings date – the Bomb Ballistics Building and the rather more mysterious but no less alliterative Black Beacon.

The Bomb Ballistics Building (looking seaward).

The Bomb Ballistics Building, looking seawards (click to enlarge). Pic: Alun Taylor

The Bomb Ballistics Building was built in 1933 as the centrepiece for a new bombing range – the rapidly increasing performance and carrying capacity of aircraft making bombing now more a science than an art.

Housing what was at the time state-of-the-art camera equipment, scientists in the blockhouse would record the flight of bombs dropped out to sea and analyse the results with a view to making design improvements.

One outcome of this research was the refinement of the design for the fins on the 5.4-tonne (12,000-pound) Barnes Wallis-designed Tallboy bomb. The accuracy of this weapon was demonstrated when it shattered the German V3 complex between Boulogne and Calais in July 1944 and destroyed the German battleship Tirpitz four months later.

Note the stilts on the Cobra Mist command building. Pic: Alun Taylor

Note the stilts on the Cobra Mist command building (Click to enlarge). Pic: Alun Taylor

The Bomb Ballistics Building was in continuous use from 1933 until the end of Orford Ness's military role when it was used for research into the ballistic properties of Britain's early atomic bombs.

A WE177 atomic bomb on display in the Information Building2

A WE177 atomic bomb on display in the Information Building. Pic: Alun Taylor

Today the roof of the Bomb Ballistics Building provides a fine panoramic view of the Ness. A pair of powerful binoculars on a 360˚ pivot gives visitors a closer look at the parts of the Ness that are off-limits to visitors.

The Black Beacon (or Maritime Navigation Beacon, to give its proper name) is a curious affair with an all-wood superstructure erected in 1928 to house a rotating loop navigation beacon.

The cover story for this site was that it was intended to provide a simple navigational aid to commercial shipping – something it actually did most successfully.

Its true purpose was to further research into radio direction finding (RDF) for military aircraft. The front was so thoroughly thought out that half of the Beacon's running costs were picked up by Trinity House Lighthouse Fund, the official authority managing the lighthouses of England and Wales.

Work on the beacon was terminated in 1934 when it became clear ground-based beacon signals could be jammed or hijacked by the enemy and that for military use it made more sense to put the transmitter for such a system in the aircraft and the receiver on the ground rather than vice versa. All remnants of the radio beacon itself have long since been removed, the inside of the two-storey tower now housing information boards and viewing windows.

Would you look at what just came across the radar?

This was not the end of RDF development on Orford Ness, though. For several years from the summer of 1935, it was the focus of the work done by Sir Henry Tizard, Robert Watson-Watt and A P Rowe, three men without whom the Chain Home radar network that saved Britain's bacon in 1940 and the radar sets that turned the tide in the Battle of the Atlantic in 1943 would not have existed.

Remarkably, the two huts that Watson-Watt and his team started work in still survive; one houses the current visitor information centre. Just beyond are the bases of the first radar transmitter masts built by Harland & Wolf in 1935. In such inconspicuous surroundings was the fate of the free world secured.

Just seaward from the Bomb Ballistics Building is one of the things that makes Orford Ness so fascinating. The entire site is littered with debris, the original use of which can now only be speculated. One such mystery is the 10-metre diameter concrete ring next to the Bomb Ballistics Building.

The mysterious concrete ring next to the Ballistics building

The mysterious concrete ring next to the Ballistics building (click to enlarge). Pic: Alun Taylor

Nobody is quite sure what it was originally built for. Some sort of radio antenna seems to be one possible answer, perhaps associated with the nearby Cobra Mist site. The dwindling number of people alive who worked on Orford Ness combined with the secrecy under which their work was conducted means we may never know.

To the south of the Bomb Ballistic Building and Black Beacon you enter the Atomic Weapons Research Establishment (AWRE) area of Orford Ness. Only a small part of this facility is open to visitors due to the risk from unexploded ordnance (a small but existent risk, I'm told bomb disposal teams are still summoned to the Ness several times a year), the state of dilapidation of the buildings themselves and the susceptibility of wildlife to disturbance.

Visitors wishing to explore beyond Lab 1 and its associated control room will need to book onto one of the National Trust's guided group tours, but these are rather infrequent and get booked up very quickly.

AWRE Orford Ness was one of only a few sites in the world where purpose-built facilities were created for testing the components of nuclear weapons. As far as we know no fissile material was ever taken to the Ness. The AWRE's concern at this site was reportedly restricted to the ballistics, detonation and environmental survivability of the bombs themselves.

Explosions, bunkers and a 20-kiloton payload

Beginning in 1953, the six large test bunkers and most of the other buildings on the shingle around them were built to carry out environmental tests on Britain's atomic bombs. These tests were designed to mimic the rigours to which a weapon might be subjected before detonation and included vibration, impact, extremes of temperature, shocks and G forces.

Drop tests of dummy atom bombs also took place over Orford Ness, the first on June 11, 1955, when a Blue Danube weapon was dropped from a Vickers Valiant V-bomber flying from RAF Wittering. The 20-kiloton payload was replaced by ballast.

Although officially no nuclear material was involved, a test failure of the initiator could have resulted in a major explosion. This is why the huge test labs were designed with pillar-supported concrete roofs and shingle revetments – to absorb and contain an accidental explosion.

The view inside AWRE Lab 1 – note the state of the roof (click to enlarge). Pic: Alun Taylor

The view inside AWRE Lab 1 – note the state of the roof (click to enlarge). Pic: Alun Taylor

Looking through a locked gate to within the massive walls of the AWRE Test Lab 1, it's easy to see why access to so much of the site is restricted. The roof, or what is left of it, is a precarious entanglement of concrete and steel and that looks ready to crash earthward at any moment. Even to the untrained eye, making the site "visitor proof" would be witheringly expensive and complicated.

The outside the AWRE Lab 1. Note the shingle piled up to contain explosions

The outside of the AWRE Lab 1. Note the shingle piled up to contain explosions. Pic: Alun Taylor

Perhaps the most distinctive buildings from this period are the two "pagoda" test labs – or AWRE Vibration Test Buildings – at the far end of the site. Their unique construction was designed to withstand the accidental detonation of 400lbs (181.4kg) of high explosives.

Sadly these are beyond the area open to casual visitors, though to be honest when I visited, apart from the occasional seagull, there was nobody to see me if I'd decided to continue down the track past the "No Admittance" sign. The entire AWRE site has been a scheduled monument since 2014.

'We couldn't tell if it was a flock of birds or a squadron of bombers. That's not ideal...'

The AWRE ceased work on the site in 1971, in some ways a victim of its own success. Despite planning and building for a substantial explosive mishap, no such thing ever occurred. Also, Britain's nuclear deterrent was taking on a less homegrown flavour with the planned introduction of the American-designed bombs and the Polaris missile system. With relatively little new work in prospect, in April 1969 the decision was announced to close Orford Ness and to move its functions to Aldermaston.

At the other end of the Ness from the AWRE site sits the brooding mass of the control centre for what was the Cobra Mist radar station. Now privately owned rather than part of the National Trust property, the command centre is not open to the public.

Built in the late 1960s at no little expense (around £860m in 2019 prices) the Anglo-American System 441A, also known as the AN/FPS-95, was planned as an over-the-horizon-backscatter radar but had a very short operational life. Plans to have the facility fully operational by January 1973 were only partly realised and the decision was taken to close the facility down on 30 June 1973.

The original hope was to track aircraft and missile launches at ranges of between 500 and 2,000 miles (about 800km to 3,200km), but thanks to the received signal being obscured by unexpected background noise, that proved to be an impossibility.

A relative of this writer who served with the US Air Force in the UK in the mid-1970s at RAF Chicksands summed it up in conversation: "We could see things in the air over the Soviet Union but couldn't tell if it was a flock of birds or a squadron of bombers. That's not ideal in a Cold War situation." Indeed.

There's still much debate as to exactly why the system didn't work – ranging from inherent faults in the design to Russian jamming. A more mundane explanation is that what primitive computing power was available at the time simply wasn't up to the task of interpreting the extremely complex and cluttered signals.

The site of the now dismantled radar array is clearly visible from aerial photography but less so from ground level, where it appears to be little more than an unremarkable expanse of scrub. The masts visible at the site today date from the BBC's later use of the site as a radio transmitting station for the Foreign Office and the BBC World Service. The BBC quit the site in 2011.

When completed, the Cobra Mist radar must have been an impressive sight: the fan-shaped array of aerials supported by a network of masts between 42 and 195 feet (13 and 60m respectively) tall covered nearly 135 acres (55 hectares). Each of the 18 antenna strings was some 2,200ft (670m) in length.

The long-term intention for the Cobra Mist site is something of a mystery. Plans to turn it into a visitor centre seem to have fallen away and there is talk of some sort of communications use or as a control hub for a wind farm or a solar power array; the site does enjoy superb links to the National Grid, thanks to the power demands of the original radar station.

One of the ex-BBC antennas is currently used by BT's mobile arm, EE – hence the unexpectedly good 4G coverage across the Ness – while another acts as a relay transmitter for Radio Caroline.

With the final departure of AWRE staff from Orford Ness in 1971, the military installations decayed. The Ministry of Defence seemed unsure what to do with the site, a situation made more complex by the bullets, rockets, shells and bombs scattered about from 60 years of weapons tests. One idea that thankfully never got off the drawing board was to build a nuclear power station there.

The National Trust moves in

In 1993, the MoD sold up to the National Trust and Orford Ness opened to visitors two years later in the trust's centenary. I've heard it said that the trust could have preserved more in those early years. The 800-yard (730m) firing range where Spitfire and Hurricane Browning .303 machine guns were first trialled is gone, as is the station headquarters and guardhouse of the original RFC base.

Had the latter been preserved, it would be possible to get a glimpse of those pioneering days of military aviation. The last WWI hangar was damaged beyond repair by gales in 1987 and subsequently demolished by the MoD. The last 20 years of MoD ownership saw the Ness pillaged by scrap metal merchants with little regard for the historic value of what they were removing.

Today the National Trust runs Orford Ness with an eye firmly fixed on the resident wildlife. The Ness is the largest vegetated shingle spit in Europe and home to some extremely rare plants. The preservation of this is naturally the trust's main focus and to this end the man-made structures on the Ness are subject to a regime of what can best be described as managed neglect, though the preferred term is wilderness management.

The restriction of visitor numbers is a practical reflection of this. Though you can walk down the shingle spit from Aldeburgh, it is a punishing trek over loose shingle and you pass two National Trust signs warning you to go no further for fear of disturbing the delicate ecology.

How long the spit from Aldeburgh will remain walkable is open to question. The sea has washed away a fair amount of the shingle so that in the places just south of the Martello tower it is barely a half dozen metres wide. The sea is also now perilously close to the foundations of the lighthouse, while the police tower nearby was washed away completely by a storm in 2012.

The spit just south of the Martello tower: one good storm and the Ness will be a real island (click to enlarge). Pic: Alun Taylor

The spit just south of the Martello tower: one good storm and the Ness will be a real island (click to enlarge). Pic: Alun Taylor

In a parish newsletter of 2015, the owners of the Cobra Mist site specifically encouraged people to see the results of recent flooding – which it blamed on the National Trust's neglect of sea defences – by walking along the spit.

The Cobra Mist site has also been subject to flooding in recent years, which is why the command building was set on stilts. Defending the lighthouse and Cobra Mist sites from the depredations of the sea runs counter to the National Trust's wildlife-focused conservation plans and reasonable belief that if it picks a fight with the North Sea it will lose.

Official access to Orford Ness is via the National Trust ferry from Orford Quay. The ferry takes five minutes and runs every 20 minutes between 10am and 3pm but not on Sundays or Bank Holidays. The size of the ferry boat and running times restricts the daily number of visitors to 156.

It's a reflection of the National Trust's policy of welcoming rather than actively attracting visitors that annually only around 8,000 people visit Orford Ness. Some of the National Trust's busiest sites can pull in those numbers on a busy Bank Holiday weekend.

Orford Ness Map

National Trust Orford Ness map (click to enlarge)

Once on the Ness, you'll be given a free map by one of the volunteer rangers. This shows the three main walking routes: Blue, Red and Green.

Blue crosses the now marshy airfield site to the information building and the other surviving structures. Red follows a parallel route but crosses the Stony Ditch which separates the marshy areas of the Ness from the shingle and then takes you to the Bomb Ballistics Building, the Black Beacon, the lighthouse and the AWRE site. Lastly, Green follows a long loop north around Kings Marsh and past the Cobra Mist building.

A section of the Red route between the lighthouse and the Black Beacon involves some heavy going along the shingle foreshore. Stout walking shoes or boots are definitely in order.

All three routes can be traversed in around three hours if you keep up a good pace but I'd add another hour if you want to stop and savour the quiet and isolation of this unique landscape and take in all the displays in the Information Building, the AWRE Control Room and the Black Beacon.

At certain times of the year, the Blue and Green routes are closed so as not to disturb nesting birds and the like. These times are predominantly in the spring and early summer but I'd advise calling the National Trust office to clarify before visiting. There are no facilities on the Ness other than a toilet, so take drinks and snacks.

Incidentally, while Orford is by no means an easy place to get to, there are a number of other interesting related attractions to visit in the vicinity – not least the Bawdsey Radar Station, which is only 30 minutes' drive away and an essential call for anyone interested in the development of radar and its role in WWII. Add five minutes to your drive and you can visit Bawdsey via the Sutton Hoo Saxon burial site. Now that's what I call a good day out. ®

Orford Quay


52.0833° N, 1.5667° E

Post Code

IP12 2NU

Getting there

By train: The nearest train station is Melton. From there the No. 71 bus takes half an hour to get to Orford.

By car: Unless you live in the area you're probably going to end up going to Orford on the A12 or A14. Once you've made your way to Farnham on the A12 take the A1094 to Orford. Just before the road ends at Orford Quay you will see an unusually large car park on your left (it was expanded to accommodate traffic used in the building of the Cobra Mist station). It's a Pay & Display affair and eight hours will cost you £4, cash only.

The quay is a very short walk from the car park. The National Trust office is on your left as you enter the quay. You will find opening hours on the trust's website.


Entry, including the ferry crossing, is £4 for National Trust members, £11 for non-members. Tickets can only be purchased on site and on the day. The £2.50 visitors guide that you can buy on the Ness from the National Trust rangers is indispensable.


This part of Suffolk is hardly short of hotels. I stayed at the Butcher's Arms in the small village of Knodishall Common. Ideally suited being only a 20-minute drive from Orford and 10 minutes from Aldeburgh. The fact it's a freehouse with a fine selection of beers was an added bonus.


National Trust site for Orford Ness

Historic England listing for Orford Ness

Recommended Further Reading

Most Secret: The Hidden History of Orford Ness, by Paddy Heazell

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