The white cliffs of Dover jut majestically towards the sky like bitten meringue, but the port beneath them is a busy, grimy place, buzzing with the hum of industrial machinery, crammed with lorries queueing to board huge ferries that chug black smoke. Even 100m up, you can’t escape the noise of the engines and drills, the broken metallic twang of public address announcements. It is not a peaceful spot.

A walking trail on the clifftop takes you to a viewpoint looking out over the yellow-green sea. The path leads past a National Trust visitor centre selling gardening gloves and ornaments, and alongside more National Trust signs that ask, “What brings you here today?” and, “Why are the white cliffs so special?” Eventually, it reaches a group of benches a few metres from the cliff edge. There are no barriers, no signs bearing the Samaritans’ helpline number (as there are 80 miles down the coast at Beachy Head), no warnings about the sudden gusts of wind that come out of nowhere and leave you unsteady on your feet. The grass is worn away where people have crept as close to the edge as they dare; but the verge itself is still green, before dropping off into a jagged white nothingness below.

On 1 January this year, a man was seen acting strangely here: lying on his belly on the cliff edge, peering over. Then, in front of families walking their dogs, he stood up and jumped. Responding to a 999 call, police and coastguard officers searched the foot of the cliffs and soon found the body of Scott Enion, a 45-year-old former soldier who had been diagnosed with PTSD. Witness reports and CCTV footage seemed to point to a clear-cut case of suicide.

But the search party were stunned to find the remains of four other people nearby: inside the harbour wall, not far from where Enion fell, lay the bodies of 59-year-old twins Bernard and Muriel Burgess. Each had a rucksack, and inside each bag were the cremated remains of two more people: their parents, Bernard and Muriel Burgess Sr.

How had the twins got there? It was quickly established that there was no connection between the Burgesses and Enion, but their deaths were a mystery. Why did they have their parents’ ashes with them? Were their deaths a terrible accident – or did they jump?

***

Detective Superintendent Stuart Ward from Kent police was tasked with working out what had happened to the twins. A solid man with broad shoulders and salt‑and-pepper hair, Ward was expecting a quiet afternoon when he left his family after lunch on New Year’s Day. He arrived for the late shift to be told a body had been found at the foot of the cliffs. Then another – and another.

They were entwined – they may even have been holding hands when they fell

“There were a few expletives at that point,” he tells me over coffee at his base in Canterbury. “Those three deaths on New Year’s Day – I think I’ve got the record for the greatest number in a single day. It’s very unusual.” Unlike Beachy Head, the white cliffs are not a known danger spot. “If it hadn’t been for those people seeing Scott Enion jump, I don’t think we would have found the Burgesses’ bodies even now.”

The twins were discovered near an engineering yard on the harbour arm that is kept locked because of the danger of rocks falling from the cliffs. Port of Dover police officers noticed a foot hanging over the top of a pile of concrete. “They went up there and found a body, which was later identified as Bernard,” Ward tells me. “But when they looked more closely and removed Bernard’s rucksack, they found Muriel underneath. They were entwined – I think they may even have been holding hands at the time of the fall.” The Burgesses were wearing waterproof outdoor gear and good walking boots. They appeared to have been there for about 48 hours.

The Burgesses were taken to a customs shed, where police went through their rucksacks and pockets to try to identify them. First, they found the two plastic carrier bags of ashes: one was quickly established as containing the remains of Muriel Sr, because the cremation slip was with it; the other was unmarked, unknown.

The walking trail along Dover’s white cliffs. Photograph: Julian Anderson/The Guardian

Bernard had his driving licence in his wallet, and was carrying bank documents that gave his address as a caravan park 300 miles away in Elton, Cheshire. There was an old chequebook with the coverslip from a previous address in Connah’s Quay, north Wales, still attached. There were also some black-and-white photographs – “family snaps at a fairground from the 50s and 60s, which would have probably been their parents,” Ward says.

Muriel carried no identification: no wallet, no bank cards. Like Bernard, she had no mobile phone. “We could identify Bernard from the photocard,” Ward says, “but I didn’t know who the lady was. Was she a partner, a friend or his sister?”

Ward contacted the police forces that covered Elton and Connah’s Quay and asked them to make inquiries. On 2 January, Kent police put out an appeal in the local and national media. Ward soon got a message to contact a woman from Surrey in her 80s, who had read about the case and thought the pair might be her sister’s children: Bernard and Muriel Burgess. “She said, ‘They live in Elton, they are inseparable, they’ve never been apart – but I don’t know what they are doing in Dover,’” Ward says. “I said I knew one of them was Bernard, and explained a few other circumstances, and she said, ‘Well, that will be Muriel with him.’”

The aunt said Muriel and Bernard had never married or had children. They grew up in Neston on the Wirral, and in 1982, when they were 24, moved to Connah’s Quay with their parents. As a young man, Bernard developed ankylosing spondylitis – a form of arthritis that left him unable to work – and lived on incapacity benefits. After Bernard Sr died in 1984, the twins became carers for their mother and never left home. When she died in 2014, they took it very badly, the aunt said. They sold the house and moved into a static caravan in Elton, a 20-minute drive away. The aunt had last seen them in July 2016 when they appeared at her door, asking to borrow money to repair a leak in the caravan – money she gave them.

No one in the family had regular contact with the twins: when the police eventually named them, they had phone calls from relatives who hadn’t seen Bernard or Muriel for years. Ward spoke to one cousin who had last seen them at Bernard Sr’s funeral. “It was almost like they had cut themselves off from their extended family,” he says.

***

If you were looking to withdraw from the world, you wouldn’t move to Orchard Park in Elton. A retirement community outside Chester, it is made up of 106 static caravans with carefully maintained gardens. They lie only a few metres apart, along forget-me-not-lined roads with names like The Firs, The Aspens and The Cedars. Everyone knows everyone. Residents often go on day trips together. Twice a year, there is a coach holiday.

“It’s lovely,” says site manager Anne Haywood. “The neighbours will do your shopping if you’re not well. They’ll come and say, ‘So-and-so’s ill, Anne.’ I’ll go and ask, ‘Is there anything we can do? Do you want running to the hospital or the doctor?’” We are sitting in her portable office at the site entrance. “See how peaceful it is? It’s a nice community, like the old days,” she says. “They’re not in everyone’s faces, but they’re there if you need them.”

But Bernard and Muriel didn’t mix, says Haywood. “They were always together. I’d never seen them separate. They used to do their shopping at night. I’d make a point of saying, ‘Hello!’ but nothing came back. It was like talking to yourself. They did not want to engage with anyone.”

It was like walking back in time to my great-granny’s flat: no telly, a wireless, passports from the 1970s

When the Environment Agency gave the park money to insulate some of the bungalows, the Burgesses were the only eligible residents to turn down the free renovations. They just didn’t want people intruding in their lives, Haywood suspects. So why move to a place like this? “It’s not dear to live here,” she says. “That’s why people retire here. They sell their house and live on the rest.” The bungalows range from £90,000 to £140,000.

Haywood says that when the Burgesses first moved in, things weren’t so bad. “I’d say, ‘Good morning’, and she’d always answer. Then she stopped answering. I thought, ‘Oh, I must have done something to upset her.’” Something changed in the two and a half years they lived here. “They became more and more reclusive. And they never had a single visitor in all the time they were here.”

On the rare occasions she saw the twins, they were always in their waterproof gear. They had sold their car and went everywhere on foot, preferring the two‑and-a-half-hour walk to Chester over the bus. “They were big walkers. Loved one another’s company. She had long brown hair; he always wore a cap. They looked liked each other. Small people.”

The Burgesses disappeared for three months last summer, and their ground rent went into arrears. Haywood thought they might have died together at home, so she called the police. They decided not to break into the caravan only because there were no flies on the windows. When Bernard and Muriel turned up again, they said they had been on a walking holiday; it was around the time when they visited their aunt to borrow money. “I said, ‘Don’t go missing like that! Just drop a note through the door. Then we won’t go looking for you.’”

Haywood thought they might have money problems. She went to the council and got forms so they could apply for assistance to cover the bills and ground rent. “I said, ‘Shall I help you fill them in? Go and sign on the dole, go and do this, you’ll be all right then.’ And they just wouldn’t take the help.” They paid their bills and no more was said.

The Burgesses’ white bungalow is the least conspicuous home in Orchard Park. The windows are smaller than those on other caravans, with net curtains or blinds, and the door number is on the side, not the front, making it hard to find. There is a washing line, a padlocked shed, some grass, few plants. It is characterless compared with the carefully maintained homes that flank it.

I am standing outside the Burgesses’ front window taking notes when their neighbour, Griff Griffiths, comes out to ask what I’m doing. This is a place where people watch what’s going on. “The curtains and blinds were always shut, even on a sunny day like this,” says 76-year-old Griff, who is wearing slippers and a blue polo shirt that shows off his faded tattoos. “If they were in the garden and saw us, they would duck down or go inside.”

He was a heart-throb, a miniature David Cassidy. And she was gorgeous: I was frightened of her

He invites me into his bright bungalow for a chat. The living room smells of freshly baked cake and the snooker is on in the background. “I used to try and make her speak to me, but in the end I gave up,” his wife Cindy says. “It was a waste of time. I thought, ‘If you don’t want to talk, that’s up to you – let’s leave it at that.’ Which is a shame. We might have been able to help them somehow.”

“They said there was something wrong with him, as if he was ill,” Griff adds. “Everything’s rumour, because nobody spoke to them. We know they paid too much for next door. Whether that did away with their money and they had none left, who knows?”

“They had the fence and the garden done,” Cindy adds.

“Yes, it certainly looked like they wanted to stay here and be happy.”

It is unlikely the Burgesses cash to spare. They were too young to claim pensions. They had sold the house in Connah’s Quay in 2014 for £115,000, only marginally more than the current cost of the cheaper Orchard Park bungalows. Letters found in their home after their deaths showed that Bernard’s disability benefits were being reassessed.

When Cheshire police knocked on Haywood’s door at 3am on 2 January and told her Bernard had been found dead with an unidentified woman in Dover, she felt sure she knew what had happened. “I said, ‘That will be his sister with him. Was it suicide?’ That was the first thing out of my mouth.”

Haywood was with the police when they broke into the twins’ home that night. “It was like walking back in time into my great-granny’s flat, honest to God,” she shakes her head. “No telly. There were two chairs, an old wireless and a table. Nothing else.” Letters from their GP, the council and the Department for Work and Pensions had been left on the table, along with two passports with blue covers, issued in the mid‑70s and long since expired. Muriel’s occupation was given as trainee secretary, Bernard’s as apprentice carpenter. The black-and-white passport photographs of the pair, in their late teens, are the only pictures of the twins police have found. “Everything was still on the table in neat little piles,” Haywood says. “To me, it looked like they knew exactly what they were going to do, and they had packed everything up.”

The only decoration was a large photograph of Muriel Sr. Nearby was an empty wooden box with an engraved metal plaque giving Bernard Sr’s name and date of death. The police could now say the unknown bag of ashes was most likely to be the remains of the twins’ father. The four sets of remains could finally be identified. Ward describes it: “We’ve got brother and sister with Mum and Dad in their bags.”

***

For James Anyon, Bernard and Muriel Burgess were Bernie and Lawley, his good‑looking, well-liked friend and his gorgeous twin sister, who attended Neston comprehensive with him in the early 1970s. Anyon can’t remember where the nickname Lawley came from. He last saw them 30 years ago and had forgotten about them until their names were made public.

The tools police use to track people – mobile phone records, debit card trails – did not apply to Muriel and Bernard

“I jumped out of my skin when I realised who they were from the news reports. You’d never have seen that coming,” Anyon, 58, sighs over the phone from the Wirral, where he still lives. “Bernie was a popular chap. The girls loved him. He was little, but he was very good-looking, as my wife has just been saying. He was a heart-throb, a miniature David Cassidy.” Anyon was in the year below the twins; he and Bernard met through a mutual friend, Tony. “Everybody got to know everybody at that time, unless you were the shy, retiring type that went into your own little shell. There were plenty of them when we were at school. But Bernie wasn’t one of them.”

The Muriel Anyon knew was “feisty”. “She was a real stunner. She used to look about 18 when she was 13. Big eyelashes. She was gorgeous. I was frightened to death of her, an older girl – you know what young lads are like. She used to knock around the park a lot. I know a couple of girls she used to hang around with. The twins didn’t seem inseparable when I knew them.”

Anyon, Bernard and their friends used to drive around the Wirral, trying to get into places that would serve them a drink. “Country clubs like the Grange or Leighton Court. We were wild in those days,” he laughs. “Bernie would have a drink and a laugh. Then he just disappeared off the radar.”

The twins were in their late 20s the last time Anyon saw them. It was after Bernard Sr had died, when they were living with their mother in Connah’s Quay. “Tony and me went to try to get the little fellow out on the razzle and it was totally strange. He wouldn’t come out of the house and Lawley disappeared into another room.” Bernard briefly let his friends into his bedroom, which was set up like a gym. Anyon says Bernard told him he had a medical condition and thinks he was trying to keep fit to fight it. “He wouldn’t come out. Lawley shied away into her room, even though she knew us. I never saw them again.”

Muriel and Bernard Burgess’s former home in a retirement community in Cheshire. Photograph: Colin McPherson/The Guardian

From what Anyon has read about the investigation into the twins’ deaths, he thinks they took their own lives, but can’t understand why they travelled to Dover. “Why would they go all the way there from Elton? It’s a hell of a long way. There are mountains you could leap out of right by north Wales, if you wanted to. Maybe that’s where their mother went on holidays, or maybe that’s where they went together, where they were at their happiest. But their mum had been dead for years, their dad even longer. Why do it then?”

How do an outgoing and popular brother and sister end up cutting themselves off from everyone? “Don’t think I haven’t thought about it,” Anyon replies. “We used to have such a great laugh. The mind boggles. But how do you know what goes on inside twins’ heads? Twins are sometimes like that, aren’t they?”

***

It takes me a while to track her down, but I finally speak to the twins’ cousin, Jo Stringfellow. Her father was Bernard Sr’s brother. She calls me from her office in Cheshire, only 30 miles from Orchard Park. She had had no idea her cousins were living so close to her; they hadn’t spoken since they were in their late teens, losing touch before they moved to Connah’s Quay and their father died.

She was the same age as them, and remembers two normal, happy children who preferred to stay at home with their mother than go out and party, as she did as a teenager. “You’d never see them separately, and they were always with their mum. Their mum was their life. She was beautiful, and their father was so good-looking. So were they,” she tells me. “We called them Big Bernard, Big Muriel and Little Bernard, Little Muriel. And they were little – they were tiny.”

Stringfellow has “absolutely no idea” why they were in Dover. She heard about their deaths only after Dover district council contacted heir-hunters, trying to find relatives who could take care of what little there was of the twins’ estate. She drove to Elton to see if any pictures of her father and their father could be found in the caravan, but there was nothing.

“I felt really sad that they lived so close to me and I didn’t know. But even if I had found them, I don’t think they would have opened their arms to me, from what their neighbours said.”

On first hearing the news, Stringfellow assumed they must have jumped. “Their mother was their life. They must have lived such a sad two or three years without her.” But then she began to have second thoughts. “Maybe it was Bernard’s bad back,” she says. “Maybe he slipped and fell and she held on to him. They were found holding on to each other, after all.

“I’m glad they both went together. If one died without the other, it would have been so tragic,” she says. “I wasn’t surprised to hear they’d never had a boyfriend or girlfriend. People talk about twins being close. It was almost like they were conjoined.”

***

The tools that police normally use to track people’s movements – mobile phone records, the trail left by credit and debit cards – did not apply to Muriel and Bernard. They had no phones and lived a cash existence. Bank records show they withdrew £200 from a cashpoint on Euston Road in London on 22 December, and they were found with a receipt for some plasters bought from Boots in St Pancras station on the same day; Ward concludes that they must have travelled to Dover around that time, before the trains stopped for Christmas. But the police have no idea how they got from Elton to London. Nothing was found on their bodies; they didn’t buy return tickets.

Ward contacted every Dover guesthouse and hotel; nobody had any record or memory of the twins staying with them. “They had no connection with Dover,” he says. “I don’t think they were staying anywhere. I think they were sleeping rough, looking at the way they were dressed. They were layered up for the elements. In their rucksacks, they had clear plastic pencil cases that contained a rudimentary wash kit – toothbrush, face flannel – so you could keep yourself fresh and clean even if you went into a public toilet and used the sink.”

On the afternoon of Christmas Day, a walker rang the police to report a man sheltering behind some large exposed rocks on the cliffs; he seemed to be either unwell, drunk or on drugs. An officer was sent to find him and discovered Bernard with his sister. “They told the officer they were on a walking holiday from the north of England and they were just resting,” Ward says. “They were both equipped for the conditions. They said they enjoyed walking various parts of the country and there was nothing to dispute that.” The Burgesses gave their names and, because they seemed to be well and not behaving strangely, the officer left them. Another receipt found with the Burgesses’ bodies shows that on Boxing Day they bought some beer, brandy and 7Up from the Co-op in Dover. After that, there is no record of their movements.

At the inquest into their deaths in March, senior coroner Patricia Harding noted that, in September 2016, the twins had visited their GP to discuss their low mood since their mother’s death; they had both refused antidepressants. Their GP had referred them to Citizens Advice because of their money problems.

The pressures of the health checks, the death of their mum, it could have all been too much for them

But the Burgesses told no one that they were going to Dover, or why, and left no note. One theory, that they had fallen while scattering their parents’ ashes, was dismissed; after all, the ashes were still in their rucksacks. Recording an open verdict, Harding said: “The evidence doesn’t disclose to the required standard of proof whether there was an intention by them to take their own lives or [if it] was indeed simply a tragic accident.”

Of all the people who knew Bernard and Muriel, from their extended family to their neighbours in Cheshire, it is Ward, a man who never met them, who probably knows most about the Burgesses’ final months. What does he think happened?

“I think…” he pauses, staring into his empty mug. “I think they fell. Knowing the cliffs, they are unstable – we have regular cliff collapses due to natural erosion. Or they could have been up there and a gust of wind blew them off the cliffs. Or they slipped on some wet grass and fell. I don’t think they went to Dover cliffs to take their own lives. That’s my personal view.

“Another person could say, actually Bernard was seeing the health professionals about his disability claim and the cuts to his benefit. Perhaps they were under financial pressure. Someone else could say the pressures of the health checks, the death of their mum, it could have all been too much for them. That might be your view. That’s why the coroner returned an open verdict.”

Ward’s explanation is plausible: the twins were walkers, appropriately dressed for a walking holiday and they fell from a popular hiking trail. But if they were simply walkers who fell, why did they have their parents’ ashes in their bags? “Perhaps they couldn’t leave home without their parents,” Ward shoots back. “Perhaps they took their parents for a walk at Christmas last year. Perhaps, perhaps. I just have to present the facts, what we know, the evidence.”

On Ward’s recommendation, the coroner has since written to the National Trust recommending that signs be placed on the cliffs warning of the dangers of falling, as well as giving helpline numbers for people in crisis.

Muriel and Bernard were cremated in Kent on 21 April, in a publicly funded funeral. Nobody present at the service knew the twins during their lifetimes; none of their relatives were there. Dover district council had already agreed that their ashes should be disposed of with the remains of their parents. It was a relief for Ward, who had no idea what to do with the two little bags of grey powder. All four sets of ashes were scattered in the gardens of remembrance at Hawkinge Crematorium in Folkestone, Kent – a place that meant nothing to the Burgess family and is hundreds of miles from where they lived. But they were together.

