Image copyright Sam Atkins

At the age of 11, Tom Gregory became the youngest person ever to swim the English Channel, driven on by an extraordinary coach. It's a little-heralded feat of endurance that won't be bettered.

It was 05:00 on 6 September 1988 and Tom Gregory stood on the tip of France. Behind him was his coach, John Bullet. In front of him was the vast, black, English Channel. Tom, in swimming trunks, faced the water. Out there, somewhere, was home.

John went to his car. He took a block of grease from the footwell and, in the glow of the headlamps, rubbed it into Tom's skin. On the water, a light appeared in the dark. A small boat came to shore. Tom put on his cap and goggles, and walked into the Channel. He followed the boat, and, when it got too deep, he started to swim. He didn't stop for 12 hours.

Tom was 11 years old.

Image copyright Sam Atkins

Tom Gregory moved to Eltham, in south-east London, when he was six. His cousins were in the local swimming club, so he and his older sister, Anna, joined as well. Most of the swimmers, says Tom, were from the council estates that surrounded the pool.

"It was very earthy," he says. "Almost all the kids were older. I was terrified."

I think John was looking for someone to break another world record. He saw this chubby boy and thought - he looks like the sort of kid Tom Gregory, Channel swimmer

The club was run by John Bullet, the manager of the local pool. He could be difficult - "old school, like Brian Clough", says Tom. But he changed people's lives.

"He used to boast - and this was the 1980s, remember - that no-one who'd been through his club was unemployed," says Tom. "By any standard, he was a world-class coach, and he was operating out of a council pool in south-east London. He took kids from estates and helped them do amazing things."

Eltham is less than 70 miles from Dover, and the club's forte was channel swimming. From 1972 to 1988, they completed 14 relays between England and France. In 1979, a 12-year-old from the club, Marcus Hooper, became the youngest person ever to swim the English Channel. John soon set his sights, well, lower.

"In hindsight, I think John was looking for someone to break another world record," says Tom. "He saw this chubby, gregarious, slightly cheeky seven-year-old boy and thought - he looks like the sort of kid."

Aged eight, Tom swam the one-mile width of Windermere in the Lake District, chosen because of its similarity to the Channel (deep, cold, and choppy). A year later, he did half a length (about 5.5 miles) and in the summer of 1987, he completed the full length, aged 10.

By this time, says Tom, Eltham Training and Swimming Club was a "movement".

"It was more than a club - it was everyone's lives. People say 'you must have had pushy parents' - but nothing could be further from the truth. They are lovely people. They just watched from the side with a mixture of fear and amazement."

After swimming Windermere, Tom began preparing for the Channel. That meant months of sacrifice, both in and out of the pool.

"People who die while swimming the Channel - and they do - tend to die of hypothermia," says Tom. "If you can handle the cold you're halfway there."

Channel swimming achievements

Image copyright Getty Images

First recorded crossing of Channel was by an Italian prisoner-of-war in 1817; Giovan Maria Salati made his escape from a prison barge in Dover and swam to Boulogne using straw as a buoyancy aid

Captain Matthew Webb made the first unassisted and observed cross-channel swim in 1875; he made landfall in 21 hours and 45 minutes

In 1926 the American Gertrude Ederle (pictured) became first woman to swim the Channel - her time was 14 hours and 34 minutes

The record for fastest-ever cross-channel swim is held by the Australian Trent Grimsey, who managed six hours and 55 minutes in 2012

Alison Streeter MBE has swum the English Channel 43 times - more than anyone else in the world

From Christmas 1987, Tom didn't touch hot water. All showers and baths were cold. From spring 1988, he slept under one sheet, with the window open. That summer, he swam a length and a half of Windermere.

"After that, I knew it was on," says Tom. "John had got me to the point where I believed it was possible. It became a burning ambition to get across."

On the evening of 5 September, he headed for Dover, fuelled by a "tray of mum's shepherd's pie". On the late-night ferry to France, he and John had a fry-up.

"These were the days before sports nutrition," says Tom.

They drove in the dark to Cap Gris Nez, the closest part of France to England. Tom entered the water and followed the small boat to a fishing trawler, which would guide him across the Channel.

Although Cap Gris Nez is only 20 miles from Dover, Tom's route was 32 miles - Channel swimmers follow an "S" shape, because of the tides.

"To begin, it's an unnerving feeling," he says. "It's dark, there's a swell. You have this real sense of '32 miles to go'. There's a real fear of failure."

But he got off quickly. By the middle third, Tom says, he was "on it".

Image copyright Sam Atkins

"I knew I was swimming fast. We got well over halfway in under five hours, so we were on for a sub-10 hour swim. That year, I think that would have got me a Rolex for the fastest swim, never mind the youngest."

Before long, Tom saw the White Cliffs of Dover. But they were almost a mirage.

"I remember the narrow band of white on the horizon," he says. "And every time I looked up, it didn't get any closer. It's mental torture. I kept my head down, kept the gaps as long as possible, but they never got nearer. And that's when the pain kicks in."

His shoulder blades, he says, felt like they were rubbing together across his back. His legs burnt. His body started shutting down.

"You know that warm and cosy feeling before you fall asleep? It's like that. You start drifting off and then you're startled by something - a foghorn, or the thud of the engine, or the smell of diesel. At one point, I remember a hovercraft coming past, and it really made me jump. You lose all situational awareness."

For most of the swim, Tom only saw John when he stopped for digestive biscuits and bottles of warm tomato soup. But in the final third, John made eye contact, and didn't let go.

Image copyright Sam Atkins Image caption John Bullet (left) talks to Tom during the swim

"He knew I was going through the pain barrier," says Tom. "He was encouraging me, but it was miserable. It feels like depression. At one point I was teary. But I was too scared to stop. Not scared of anybody - just scared of not completing it."

Eventually, the White Cliffs became closer. As they approached the shore, the trawler stopped, and John jumped in the small boat to guide Tom home.

"It's strange - I'd been so exhausted, but for the final five or 10 minutes, I powered to shore. It was like I was on autopilot. I remember John in the tender just shouting 'Go! Go! Go!'"

Tom swam towards Shakespeare Cliff, a shingle beach to the west of Dover. About 20 people, including his parents, were watching. Eventually, Tom saw pebbles. For the first time since Cap Gris Nez, there was land beneath his feet.

He put one foot down. Then another. He stopped swimming.

He had made it from France to England in 11 hours and 54 minutes. He was 11 years and 336 days old. No one has done it younger, and no one ever will. In November 2000, the Channel Swimming Association banned under-16s from attempting the crossing.

Image copyright Sam Atkins Image caption Tom Gregory with John Bullet (centre right in hat)

"When I reached the shore, I was a few notches off compos mentis," he says. "I was dazed, confused. I'd been in cold water for 12 hours, with a high rate of exertion. I'd been told you had to take three unaided steps after reaching land, otherwise you hadn't made it. But I couldn't stand up. I was on my knees.

"Those steps became massively important. It was a Neil Armstrong moment. Eventually I did three steps, and I sat down. I remember being surrounded by people cuddling me."

After warming up, Tom and John headed on the trawler to Folkestone harbour, where television crews were waiting (only the Evening Standard made it to Shakespeare Cliff).

He appeared on ITN and Blue Peter, where he was given a gold badge ("awarded in exceptional circumstances for outstanding achievement"). He even made the New York Times.

"But, once the fuss died down, I didn't really talk about it," says Tom. "John didn't want me to become a big head."

Tom, now 39, went on to university and then Sandhurst, becoming an officer in the Royal Anglian Regiment. He served in Iraq and Afghanistan, and now works for accountancy firm Deloitte, living in Surrey with his wife and daughter.

Image copyright Tom Gregory Image caption Tom Gregory today: "I do still swim, but not enough as I should. Adult routines somehow get in the way."

After swimming the English Channel, John and Tom discussed swimming the Irish Sea between Northern Ireland and south-west Scotland, as well as the Thames, and a relay of the Lakes, travelling between them on helicopter. There was also talk of Olympic training.

If John Bullet was alive today, he'd be getting Unsung Hero Award at the Sports Personality of the Year Tom Gregory

And then, five months after Tom broke the record, John died. He was 50.

"He was at the baths, five o'clock in the morning as usual, and he had a massive stroke," says Tom. "He never recovered. He went to hospital and there was a constant procession of people by his bed. Kids who he helped over the years - families whose lives he'd changed. People who loved him.

"For me, it was like losing a father. It ruined me. I used to spend so much time with him. I remember being in school, singing a hymn, and bursting into tears."

According to an Eltham newsletter, more than 300 people attended John's funeral, "despite the fact he had no family at all".

"If John Bullet was alive today, he'd be getting Unsung Hero Award at the Sports Personality of the Year," says Tom. "He did countless relays of the Channel, and broke two world records, all with kids from a two-mile radius of Eltham Baths. It was incredible. But when John died, the club sort of died. It lived on thanks to some very selfless people, but my connection went.

"This isn't false modesty, but the Channel swim wasn't about me. It was about the club. I was part of a movement, and I represented all of us. It only happened because of the courage and vision of John. I guess I was the lucky one who got the challenge."

The crack-of-dawn starts, the hours in the pool, the weeks in Windermere, the cold showers, the open windows, the burn, the pain, the tears. Could any child enjoy that?

"Oh yeah," Tom says, surprised at the question. "I loved it. That club changed people's lives."

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Image copyright Getty Images

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