Secrets and spies: Behind the doors of the UK's most enigmatic government agency

Over a century GCHQ has evolved from a codebreaker into a critical defence against the most advanced technological threats to national security. And while changes are afoot, some old habits die hard.

By Dominic Bliss
photographs by Jonny Pickup
Published 5 Oct 2020, 16:51 BST
GCHQ (Government Communications Headquarters) has long been tight-lipped about its work safeguarding the nation. Modern times ...

GCHQ (Government Communications Headquarters) has long been tight-lipped about its work safeguarding the nation. Modern times bring new challenges – and controversies. 

Photograph by Jonny Pickup, National Geographic

THEY CALL IT 'THE DOUGHNUT:' 180 metres in diameter, this massive circular building in Cheltenham houses GCHQ, the government’s intelligence, cyber and security agency. It’s here that some of the country’s greatest hackers, technophiles and spooks ply their trade in espionage. 

As you’d expect, media visits are rarer than hen’s teeth. When National Geographic UK is invited, the security protocol is reassuringly stringent: a sort of Checkpoint Charlie in the Gloucestershire suburbs.

Once our ID has been checked at the main entrance, we drive at snail’s pace through no less than three security gates before parking at the visitor’s entrance. Here we undergo a body and bag x-ray search and are photographed for our security passes. Much more follows in the same spirit before we find ourselves inside the main building. It's enough to say even the craftiest of criminals couldn’t sneak into this fortress.

The 'ring of security' is literally thus: a circular building that contains everything its employees need for a long shift. The offices operate 24 hours a day.

Photograph by Jonny Pickup, National Geographic

And just as well, for GCHQ (Government Communications Headquarters) is the agency charged with keeping our nation safe. Employing around 10,000 people, it also includes the National Cyber Security Centre, based in London. Around half the employees work at the Doughnut in Cheltenham, the other half scattered at stations in London, Manchester, Bude (in Cornwall), Scarborough and RAF Menwith Hill (in North Yorkshire), RAF Digby (in Lincolnshire) and, it's widely rumoured – although the agency won't admit it – in various British Overseas Territories and foreign countries. “The sun never sets on GCHQ’” is how one employee describes it.

The mission

On the agency website, director Jeremy Fleming explains the key functions: “We focus on communications: how to access, analyse and – occasionally – disrupt the communications of the UK’s adversaries; and on the nation’s cyber security.”

He pinpoints what he calls the “mission areas”. These are: preventing terrorist attacks, cyber security, thwarting serious and organised crime, supporting the armed forces, and something called strategic advantage - which includes “managing threats from hostile states, promoting the UK's prosperity and shaping the international environment”. 

But what does all this snooping around in the shadows actually achieve in the real world? Asked to provide details, the agency is understandably tight-lipped. They do, however, give the following examples: between 2018 and 2019 they helped foil 19 terrorist attacks, and prevented around £1.5 billion of tax evasion; they contributed to the arrest of sex offenders Matthew Falder and James Alexander; in 2018 they conducted a cyber campaign against ISIS, “hindering their ability to coordinate attacks, and protecting coalition forces on the battlefield”; in 2020 they exposed Russian attacks on the development of coronavirus vaccines.

Other crucial GCHQ work – as we discover when our tour starts with a briefing in the director’s meeting room – includes protecting British citizens, businesses and institutions from cyber attack, and defending the nation from the at times provocative governments of Russia, China, Iran and North Korea, for example.

“Staff must agree to keep their identities very low profile... An employee explains: “Where we work isn’t secret; what we do is.””

GCHQ staff, going about their day. Nothing more can be said – and this goes for their daily lives, too.

Photograph by Jonny Pickup, National Geographic

Our briefing comes from a long-serving stalwart of the agency; he's called Paul. For security reasons, all but a handful of employees here – such as the director – are known only by their first names.

Paul vehemently stresses how all intelligence gathering must be “legal, ethical, warranted and necessary”. (American whistle-blower Edward Snowden, who exposed mass surveillance by GCHQ of private data and communications, might disagree with this.) 

Paul says staff must agree to keep their identities very low profile. The few who have a social media presence, for example, might simply list themselves as “civil servants”. But since the agency is one of the largest single employers in Gloucestershire, locals often know if their neighbours work at the Doughnut. As another employee explains: “Where we work isn’t secret; what we do is.”

Nevertheless, it was only in 1982, when the then prime minister Margaret Thatcher first mentioned GCHQ in parliament, that the agency’s existence was officially acknowledged. Before then, the public impression of Britain’s spying agencies was left to fiction writers like Ian Fleming, Graham Greene and John Le Carré

Non-fiction writers weren’t so tolerated. So cloak-and-dagger were the goings-on in Cheltenham that, in 1976 for example, when an American journalist wrote an exposé on the agency for Time Out magazine, he was subsequently deported as a threat to national security. 

Out of the shadows

Times have changed since then, though. During the last decade GCHQ has emerged from the shadows and is now actively recruiting a more diverse workforce. Having its base in the very bourgeois environs of Cheltenham probably doesn't help. One of the reasons the agency recently opened a new station in Manchester was to attract employees from varied backgrounds, perhaps realising that a diversity of social class, race, language and neurodiversity can only help in the business of spying. It now has social media feeds, and publishes GCHQ-branded puzzles for the public.

Communications has always been a lynchpin of GCHQ. But in the modern world of cyber warfare and data hacks, the agency's work has never been more critical – or scrutinised.

Photograph by Jonny Pickup, National Geographic

Spying in the digital age requires a new generation of skills. A recruitment advert for the agency's Computer Network Operations team describes a role that “hacks the computers of terrorists and criminals to discover and disrupt their plans.” 

Photograph by Jonny Pickup, National Geographic

That doesn't mean the agency has softened, though. From the director’s meeting room, our tour moves to the ‘Event Management Centre’, where senior operations officer Caroline explains how staff work 24 hours a day, ready to coordinate a response to crises such as terrorist attacks or kidnappings. 

Around the outside of the room there is a ring of eight clusters of desks, known as huts – a nod to the old days when code-breakers used to work in wooden huts at GCHQ’s former home at Bletchley Park. Framed above these desks are ticker-tape screens blinking with the different time zones of the agency’s allies around the world. ZULU is Greenwich Mean time; NSA is the US National Security Agency in Maryland; ASD is the Australian Signals Directorate in Canberra. There are also dozens of TV screens. Some feed through the main British TV channels, but for security reasons, others have been switched off before we enter the room.

The tour continues downstairs. The Doughnut comprises two concentric circular buildings, with a covered walkway in between known as The Street. It’s a design that allows employees to move around the building as rapidly as possible, the idea being that no one is ever more than five minutes’ brisk walk from another colleague’s desk. 

Lining The Street are all the facilities employees might need – a Greggs, Costa Coffee, Starbucks, a convenience store, a staff canteen – ensuring they can remain inside the security ring for entire shifts. Also here is a small museum housing infamous security items such as the Enigma machine which helped the British decipher German codes at Bletchley Park during World War II; and the Zimmermann Telegram, which proposed a military alliance between Germany and Mexico during World War I, and hastened USA’s entry into the war after it was intercepted by the British. 

In the very centre of GCHQ is an open-air garden which, according to our guide, is large enough to accommodate the Royal Albert Hall. There are a dozen or so deckchairs scattered across the lawn, a glass pod in which to sit when it’s raining, and a smoking shelter. On the far side is a monument to the employees of GCHQ who have died in the line of duty, although we are not permitted to examine the names inscribed on it.

“We save people’s lives, we stop bombs going off, we stop army units being killed in Afghanistan. If that doesn't motivate you to get to work in the morning, I don't know what does.”

David Abrutat

Dr David Abrutat in the server room, GCHQ. The organisation's newly-appointed historian, David is one of a handful of 'avowed' employees – meaning he is authorised to reveal his name and face to the public.

Photograph by Jonny Pickup, National Geographic

Only one member of staff's identity is offered up, and for the first time in his case: Dr David Abrutat, GCHQ’s newly appointed historian. Along with the director Jeremy Fleming, he is one of just a handful of “avowed” employees, meaning he is legally permitted to reveal his face and full name to the public.

A former Royal Marine Commando and history writer, he was drawn to the job through his passion for military history. His role grants him access to all the agency’s historical archives – even the top secret stuff the public will never find out about. “A treasure trove,” is how he describes it. “For me it's like going into a sweet shop.”

Some of the secrets stored by GCHQ are released to the public 30 years after they happen. But not all. “We are not obliged to release them,” he confirms.

A history in artefacts

Sitting in his wheelchair – a consequence of a car accident 20 years ago – Abrutat proudly displays some of his less sensitive documents and objects. The oldest item in the archive is a Foreign Office parchment from 1809 which explains to overseas diplomats how to encipher their communications. 

Dated 1915, there is a telegram from the British Admiralty to the Royal Navy, reporting on German U-boats in the vicinity of the British ocean liner RMS Lusitania, just hours before it was sunk – an atrocity that drew the United States’ into World War I.

Lined with lead, a Royal Navy codebook from World War II feels strangely heavy in Abrutat’s hand, he says. It was designed so that, should enemies board the ship, the captain could quickly drop it overboard to the bottom of the sea. 

From a more modern conflict – the first Gulf War – there’s an Iraqi radio receiver, its casing battered and worn away by desert sand.

The smallest item is a personal diary of the first head of GCHQ, Alastair Denniston. Abrutat points out the entry for December 8th 1941, where Denniston has written just one word in capital letters: ‘JAPAN’. “That was the day after the Pearl Harbour attacks,” he points out.

A century of work has left the agency with a legacy of fascinating documents describing key events and communications from the biggest wars in history – to personal items from key figures within them.

Photograph by Jonny Pickup, National Geographic

David Abrutat describes the documents he works with as GCHQ's historian as ‘a treasure trove.’

Photograph by Jonny Pickup, National Geographic

Finally there’s a German Lorenz cipher machine which was captured in 1945 in occupied France and driven straight back to Bletchley Park. “These machines were used by German High Command and by Hitler,” Abrutat says. “In the run-up to D-Day, Bletchley Park was really interested in the German communications between Paris and Berlin; everything that was going on in Normandy. It was an insight into what Hitler was thinking.”

GCHQ has existed for over a century now – plenty of time to accumulate many such documents and souvenirs from the world of espionage. The agency traces its origins back to November 1919 when, following the success of army signals intelligence during World War I, a new peacetime intelligence unit, called the Government Code & Cypher School, was established at Watergate House, in central London. 

During World War II the organisation moved to Bletchley Park, in Buckinghamshire, changing its name to GCHQ. After a brief spell at Eastcote, in the London suburbs, operations relocated to Cheltenham in 1951. In 2003 GCHQ occupied its current home in The Doughnut.

A rare SG-41 (Schlusselgerat 41) cipher machine stands next to a photo of Admiral Wilhelm Franz Canaris. Canaris turned against Hitler towards the end of the war and was executed for his involvement in the assassination attempt against the German leader in 1944. 

Photograph by Jonny Pickup, National Geographic

Abrutat explains the value of history in educating the public about GCHQ’s role in national security. Occasionally he and his staff offer tours of the museum to schoolchildren and VIPs. He’s also collaborating with an author on an official history of the agency, due to be published in October 2020. 

“It’s all about selling us as an organisation, and recruiting the next generation of analysts, linguists and cyber ninjas,” he says. 

But history is also vital in educating today’s new recruits. For that reason Abrutat documents previous GCHQ missions, in the hope that current employees might learn vital lessons from them. 

“We’re not very good at learning lessons; most organisations aren't,” he says. “But having a corporate record of why we made a [certain] decision in 1977 or 1984 – you can use that to educate future management and leadership; so as not to trip up again.”

Intelligence and espionage are continually evolving. This, says Abrutat, is what keeps him and his colleagues at the Doughnut focussed on their missions.

“We save people’s lives, we stop bombs going off, we stop army units being killed in Afghanistan. If that doesn't motivate you to get to work in the morning, I don't know what does.”


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