The heroes who’ve conquered Britain’s HEART of DARKNESS
They famously helped rescue the Thai boys trapped in a cave. But their biggest challenge of all was to crawl, swim and climb through the longest underground journey ever made in the UK... and the Mail was there to help them
The prospect would terrify most people: plunging into a series of pitch-black caverns riddled with tight crawlways, underground rivers, vertical shafts up to 150ft deep and numerous ‘sumps’ — long and deep underwater tunnels so murky that, even if you had a powerful light, you couldn’t see a hand in front of your face.
But Chris Jewell and Jason Mallinson were about to do just that in a recordbreaking bid to complete the longest-possible journey in underground Britain.
We were standing at the easternmost entrance to the lengthiest caving route in the country through the 54 miles of the Three Counties System, which snakes its way through North Yorkshire, Lancashire and Cumbria.
high on the slopes of Gragareth, a heather-clad fell in the Yorkshire Dales, the vertical opening takes you down to a cave known as Large Pot.
Down there, is British caving’s holy Grail. This extraordinary bid to conquer it was the culmination of almost 100 years of exploration during which new caves were discovered and routes joined together — often by diggers who poured years into clearing blocked passages — to offer the adventurous the nation’s biggest underground journey.
While completing it, the cavers had to swim more than a mile underwater, through seven separate sumps; they had to bend their bodies past the tightest turns, at times inching their way forward in desperately confined spaces on a journey of seven miles and more.
The skill and stamina involved over nearly 20 hours had — until now — been considered beyond even the best in the business.
It is little wonder that Jewell admitted to being ‘a little apprehensive’, adding: ‘If we pull this off, it will be a once-in-a-lifetime trip.’
HE SMILED . . . then suddenly disappeared down the rope, swallowed up by the earth. Jewell, 39, an IT consultant from Cheddar in Somerset, and Mallinson, 53, a rope-access technician who lives in huddersfield, are both veteran cave divers.
The pair were suddenly propelled to worldwide fame three years ago when they played critical roles in the rescue of the 12 boys and their football coach from the flooded Tham Luang cave in Thailand.
On three successive days, both men dived through a mile of underwater tunnels to the chamber where the boys were trapped.
The 13 were carried out one by one, a heroic feat that is the subject of two feature films: The Rescue, a documentary by Oscar-winners elizabeth Chai Vasarhelyi and Jimmy Chin, due out next month; and Thirteen Lives, a drama version by Apollo 13 director Ron howard, to be shown next year.
The Thai rescue had the highest-possible stakes. But the sheer difficulty of what the two men were attempting last weekend — starting on Saturday — was far greater.
‘In terms of the caving, this is harder,’ said Mallinson. ‘The dives are longer and deeper, and the water is much colder. And there’s a lot of tiring, dry passage.
‘On the other hand, not having the responsibility of trying to swim while carrying an anaesthetised child does make a difference.’
Until last weekend, no one had seriously thought of doing it in one go. It was too daunting.
When Mallinson and Jewell entered Large Pot, they faced not just those seven miles of caving, of which a mile-and-a-third was underwater. But also the seven sumps, the longest of which had never been dived end to end.
The record attempt required a vast logistical effort to transport diving gear to different spots and stow it along with food, to rig the vertical sections with rope and then, starting on Sunday, to pull the equipment out again.
On Saturday, about 50 cavers were involved in supporting roles — including me. Kevin Gannon, 62 and Secretary of the northern section of the Cave Diving Group, came up with the master plan. A further 20 played their part in preceding weeks.
At the team briefing in a car park in the North Yorkshire village of Ingleton, beforehand, he likened it to an ‘underground K2’, a reference to the pyramid-shaped mountain in the himalayas that is considered the ultimate challenge for the world’s best mountaineers.
‘But after the months of lockdowns,’ he added, ‘what a great way to bring British cavers together, and to put us back on the world caving map — so long as nothing goes wrong.’
Some of the toughest dry caving is early on, through the narrow crawls between Large Pot and Ireby Fell Cavern.
Before committing themselves to the attempt, Mallinson and Jewell had to visit them to make sure their bodies were small enough to force their way through.
Jewell is a slim, very fit man. ‘It was snug, even for me,’ he said.
Caving photographer Bartek Biela, his wife Paulina and I were planning to meet the pair three times, the first as they emerged from a sump at the end of a cave called Notts Pot 2.
We descended its vertical entrance shaft into a long section of underground river, well over half a mile long, with an arching tunnel and a gleaming, crystal roof.
At the upstream end we stood by a pool where the roof dipped beneath the water’s surface — a sump.
After a few minutes the thin nylon line laid through it — the vital thread that cave-divers grasp in order to navigate when the water is too murky to see — began to twitch. Someone was coming.
AFeW seconds later, we saw two golden, shining orbs underwater — the divers’ helmet-mounted lamps. First Jewell, then Mallinson, broke surface. They changed from their neoprene diving gear into dry caving kit (fleece one-piece undersuits and waterproof PVC coveralls) brought in by the support team.
‘It’s going well,’ Mallinson said, grinning broadly.
We were hundreds of feet below ground — and I was conducting my first underground interview for the Mail. Then they were off again.
Bartek, Paulina and I made our way out and slogged across the hillside to the next place we planned to meet, Shuttleworth Pot, where we abseiled into a huge, echoing cavern with a river and a rumbling cascade.
For Mallinson and Jewell, this would offer only a brief respite, between their two longest dives.
The first — a 900-yard swim from Lost John’s Cave — had never been attempted as a ‘through dive’ before.
It was Mallinson who first connected the line from Shuttleworth to one laid earlier by divers from Lost John’s, but he hadn’t gone all the way from end to end.
We waited. And we waited. We were damp, and the chilly air of the cave began to penetrate. After nearly two hours, our anxiety was growing. But at last, the line twitched and there they were.
For the longer dives, Mallinson and Jewell were using ‘rebreathers’ — high-tech units that allowed them to carry less bulky gear.
The machines recycled exhaled carbon dioxide by ‘scrubbing’ it with a chemical, allowing the air to be reused.
But halfway through the sump, with a lot of water and solid rock
above his head, Mallinson’s unit malfunctioned, an event he with detached, matter-offact calm.
One of the unit’s automatic valves was feeding too much oxygen into the system, overinflating his lungs and giving him ‘hamster cheeks’.
If he hadn’t been able to deal with it, it could have made the rebreather impossible to use — and if he’d panicked, he might have drowned.
If their equipment fails, cave divers can survive only if they remain icily calm.
‘I just turned off the valve and did its job manually instead,’ said Mallinson.
he still had three more sumps to go and would have to stick to this more demanding method throughout, but giving up was ‘not an option I contemplated’, he said.
We carried the divers’ gear through a short, low passage to the next sump, where the river emerged.
The divers sat by its bank, sipping hot Ribena and munching energy bars.
after just a few minutes they got into the water, adjusted their gear and vanished once again.
They still had a long way to go. We encountered them a final time hours later, after their last, punishing dive.
Now it was after midnight, and they looked tired.
‘The last five hours were pretty tough,’ Jewell admitted. ‘apart from the distance we’d travelled, my body was telling me this was the time I should be asleep.’
Five hours later, 17-and-ahalf hours after entering Large Pot, they emerged from Top Sink on to the Cumbrian fell.
They’d made it! There was a reception committee — and celebratory beers.
‘I’m glad it’s over. It was hard,’ Mallinson said later. ‘It wasn’t the diving, even though in places the visibility was only 5cm, but all that crawling.
‘I feel elated and privileged,’ Jewell added. ‘It was incredible to have so many people willing to help us.
‘and some of the links between the different entrances took years of hard work, by diggers removing rocks and mud from passages that had long been blocked. We were building on a lot of work.’
Meanwhile, hopes are high among cavers that eventually, a way will be found to connect the Three Counties system with the 20km network that lines both sides of the next valley to the east, Kingsdale.
This will create the scope for an even longer and more arduous trip.
‘If it happens, I’d love to be part of it,’ said Jewell.
‘What we’ve done is the most demanding trip in British caving, but I’m very much hoping that won’t always be the case.’