It was all gone. The lanes of gritstone cottages, the church and old schoolhouse, the sheep grazing on hillsides and the sloping pastures. Derwent Valley Water Board had, despite protests, flooded the valley and the village of Derwent to provide water for the growing cities in the English Midlands. By 1945, Derwent village no longer existed and in its place lies a sheet of blue: Ladybower Reservoir.

After completing the dam needed to create the reservoir in 1943, rains, mountain run-off and rivers filled the valley – and slowly, the waters rose. From then on, nothing of Derwent was visible, except for the ghostly church spire that poked out of the reservoir during dry periods when the water level dropped.

At these times, locals would return to gaze at the eerie spectacle in morbid fascination, as if to remind themselves the village had once been a reality. Some swore they could hear the church bell ringing out across the waters – although the bell had been removed before the village was drowned.

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Before the two World Wars, Derwent and nearby Ashopton village had seemed as permanent as the Peak District moorlands above them, with their centuries-old stone buildings and long-established communities. The Water Board had earmarked an isolated area higher up the valley to create two initial dams and the Howden and Upper Derwent reservoirs, and the small number of residents from affected farms and smallholdings were moved down the valley to safety at Derwent and Ashopton. No-one dreamed that this part of the Derwent Valley, with its two beautiful villages, would soon be flooded, too.

Creating the first two reservoirs was a huge undertaking: relocating residents; organising a workforce; preparing the ground; laying pipes; building bridges and dam heads. A new, temporary village sprung up nearby to house the hundreds of workers.

The town was named Birchinlee, nicknamed “Tin Town” as the buildings were made of corrugated metal – easy to both erect and dismantle after the reservoirs’ completion. Despite its short-lived existence, the model village had every facility: a hospital, school, canteen (that also served as a pub), post office, recreation hall, bath house and railway station. It even had a police station. By 1912, Howden was finished, and the Upper Derwent Reservoir below it, four years later. The hundreds of workers and their families packed up and left. Tin Town was dismantled, metal sheet by metal sheet.

Soon, the Water Board realised that Howden and Upper Derwent reservoirs were not meeting the demands of the growing English Midland cities like Sheffield and Leicester. A third reservoir, Ladybower, was approved to be built further south, even though the villages of Derwent and Ashopton stood in the way of its construction – they would simply have to be flooded along with the valley. Work on Ladybower began in 1935, and the affected villagers were again relocated to other areas.

By the time I moved to the Peak District in 2000, there was little evidence Birchinlee had ever existed. Undeterred, I set off one early summer’s day a few years ago in search of Tin Town, following a ruler-straight grassy path beside Howden Reservoir and on through trees where a railway track had once lain.

There was no sign of the tin huts; only their stone foundations remained. However, information boards erected along the railway line clearing showed a series of black-and-white photographs of the temporary residents at work and at play in front of the tin huts, with explanatory captions beneath. There were pictures of navvies – the itinerant workers – busy on the construction sites, women and children washing clothes outside modest dwellings and families posing in surprisingly homely interiors.

I learned that one of the huts had been reassembled in the nearby village of Hope, and found this last remnant of Tin Town squeezed between buildings down a side street, the tiny corrugated hut now a modest hairdresser. I was also able to hunt down the village packhorse bridge – a handsome humpbacked bridge – reassembled at Slippery Stones, where it spans the river at the head of Howden Reservoir. The bridge had been moved there, stone by stone before the flooding.

Having explored the sites of Birchinlee and Slippery Stones, I hoped the submerged ruins of Derwent would reveal themselves soon, as they sometimes do during dry spells. Derwent had made a brief appearance in the long, dry summer of 1976, and once in each of the following decades, most recently in 2003. Ashopton, the second sunken village, also lay undisturbed under the water, but I knew there was no chance of ever seeing it as it’s now buried beneath silt. But what remained of Derwent beneath Ladybower?

Luck was on my side. In 2018, a hot, dry summer descended on the area. The waters of the reservoir fell, and fell again, until the remaining stones of Derwent emerged from the mud-caked banks.

By the middle of September, the ruins of Derwent Church were exposed. Nearby, cottage doorways, hearths and lower walls revealed themselves. The reservoir level continued to drop and I could walk out to the ruins of the stately home of Derwent Hall, stepping gingerly across the muddy reservoir floor in the autumn sunlight. Among the rubble, an imposing stone fireplace with its rounded columns was still largely intact, and the building’s ornate gatepost rose out of the water behind it. Wandering through the debris, I imagined the lives that would have gone on within the big house’s walls.

The path beyond the church that led to the school was also exposed, along with the little bridge that crossed the stream to the schoolhouse and its gateposts. There was an eeriness and melancholy in the piles of blackened stones. This sight was far removed from the sepia pictures I’d seen of the village: schoolchildren wandering along a leafy country lane in straw hats and smocks; boys loitering by a stream below cottages; villagers bent over the bridge in front of the big house. Old photos of Derwent Hall revealed a grand panelled drawing room and ornate ballroom.

Was there anyone left, I wondered, who remembered the lost villages of the Upper Derwent Valley? Someone who could breathe life back into the damp, crumbling ruins?

A friend pointed me in the direction of 92-year-old Mabel Bamford, who lives in the village of Bamford south of the reservoirs. Mabel welcomed me into her home with an energetic step and sparkling eyes.

“I may be the last person who remembers Ashopton and Derwent,” she said cheerfully.

I may be the last person who remembers Ashopton and Derwent

Bamford beckoned me to sit down, eager to begin her story.

“When Rose Cottage in Ashopton came vacant, my parents moved there, and we lived in the village until 1938.”

“What do you remember about life in Ashopton?” I asked.

“I remember our cottage was very simple. There was no electricity, just a paraffin lamp in the living room. Candles were used everywhere else. The loo was an earthen closet a long way from the house.”

I nodded, recalling the accounts I’d read of villagers rehoused by the Water Board in homes with modern bathrooms. It had made the move easier.

“And what about Derwent village, Mabel? Do you remember it?”

“Oh, yes, I was going to school there, even as the construction of Ladybower was underway. We had to walk one-and-a-half miles to Derwent. Sometimes the shooters and beaters in grouse season gave us a lift. But the rides we liked best were offered by the pipeline workers. They’d lift us inside the big black pipes they were constructing at the site of the reservoir,” she said.

I nodded. I had noticed the large pipes that span Ladybower at Fairholmes, where the visitor centre sits at the head of Ladybower. They were easily big enough to hold a child.

“I remember in the cold weather there was always a fire lit at school,” Bamford continued. We’d bring a big potato with our initials carved into it and Teacher would bake them for us and make us cups of cocoa.”

Bamford told me more stories: of the policeman who came to her house to berate her for stealing apples; and of the excitement in Ashopton when the petrol station owners generated electricity with a windmill-like contraption. And how the Derwent young men walked to the Methodist Church at Ashopton to scrounge for food at their social gatherings, rechristened the “Bachelors’ Tea” as a result.

I left Bamford, feeling privileged to have heard her first-hand stories of the drowned villages. I’d been offered a glimpse into the past firstly with Derwent's reappearance, and again with Bamford.

One year on, the ruins of Derwent village have returned to the murky depths of Ladybower Reservoir. I’m now left wondering: will Derwent village stay hidden for another decade or more? Or with climate change, will its resurrection become a regular occurrence? I will have to wait and see.

Sunken Civilisation is a BBC Travel series that explores mythical underwater worlds that seem too fantastical to exist today but are astonishingly real.

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