The Wonders of Pontneddfechan: A Journey Through Waterfall Country & Glynneath Gunpowder Works
- Jay Curtis
- May 23
- 8 min read
Nestled in the southern reaches of the Brecon Beacons National Park, Pontneddfechan. This enchanting village offers a blend of natural beauty, geological marvels, and rich industrial heritage, making it a must-visit for nature enthusiasts and history buffs alike. My latest walk took me deep into the heart of Waterfall Country, where history, geology, and folklore collide in spectacular fashion.
Sychryd Waterfall and Gorge:
I parked up near Dinas Rock, a popular starting point with easy access to several trails. From here, I followed a short trail from the car park which leads to the mesmerising Sychryd Waterfall. This steep path meanders between the Afon Mellte and the River Sychryd, culminating in the stunning waterfall.
The gorge is narrow and dramatic with sheer cliffs rising on either side, carved over millennia by the relentless flow of water. The highlight is undoubtedly Sgydau Sychryd, a beautiful waterfall framed by rock and forest. It’s not the tallest, but its setting is almost theatrical. I stood watching for a long time, the water catching morning light like silver threads. What struck me most was the tranquility, even with a few fellow walkers around. It's a place that feels suspended in time.
Dinas Silica Mine:
Just beyond the waterfall, tucked behind the trees, lie the remnants of the Dinas Silica Mine. In the 19th century, this was a bustling industrial site, extracting high-purity silica used in furnace linings across Britain’s metal industries.
Workers here quarried a very pure form of silica-rich sandstone, which was crushed and shaped into what became known across the world as Dinas firebricks. What made these bricks so special? Their exceptional resistance to heat. While ordinary bricks would crack or crumble under the intense temperatures of smelting furnaces, Dinas firebricks could withstand over 1600°C. This made them invaluable to the iron, steel, copper, and glass industries – not just in Britain, but around the globe.
They lined the insides of blast furnaces in South Wales, Scotland, Germany, the United States, and beyond. Even today in Russia, the name Dinas firebrick remains and without them, the furnaces that forged modernity would have been far more limited in power and longevity.
At the height of production, hundreds of tonnes of silica were extracted from beneath Dinas Rock and shaped into bricks in local kilns. It was harsh, dangerous work. The miners and brickmakers toiled in difficult conditions, with long hours, intense heat, and ever-present risk. Many would have lived in the surrounding valleys, their families relying on this tough trade to survive.
Walking inside the mine, you can still see the scars of industry carved into the landscape. Large caverns and transport routes remain etched into the hillside. It's humbling to think of the global impact this remote Welsh gorge once had – a quiet corner of the Brecon Beacons providing the literal backbone of the industrial world.
Today, nature is reclaiming the site but the past feels close underfoot.
Arthur’s Cave:
High above the gorge, carved into the limestone mass, lies a small but storied opening known as Arthur’s Cave. On first glance, it might seem like just another crevice among many in the rugged rockface – but this cave is woven into the very folklore of Wales, and for centuries, it stirred imaginations far beyond the valley floor.
Local legend holds that this is one of several places where King Arthur and his Knights of the Round Table hid in secret. According to the tales, they slumbered in a great cavern beneath the mountain, waiting for the moment when Wales needs them most. One day, it is said, the mountain will split open, the warriors will rise, and Arthur will lead them once more. These stories have passed through generations, whispered in farmhouses and echoed in schoolyards – until, in the late 1800s, something remarkable happened that seemed to suggest there might be some truth buried beneath the myth.
In 1860, a man named William (or Wills) Morgan, a local explorer and self-styled antiquarian, claimed to have discovered an extensive cavern hidden inside Craig-y-Ddinas. The find made headlines across Wales and even appeared in Victorian newspapers under headlines like “The Cave of Arthur: A Legend Proved True?” and “Sleeping Warriors Beneath the Rock.” Morgan described descending through a narrow fissure into a larger chamber, where – astonishingly – he claimed to have seen stone benches, what appeared to be old weaponry, and even a large stone table. Some accounts said it was “round like in the legends.” It fuelled the romantic idea that Arthur’s knights truly waited there in enchanted sleep.
Skeptics, of course, dismissed it as fantasy or exaggeration. There were no photographs, and Morgan was known for a flair for the dramatic. But the fact that a real cave exists – and that it is reachable with a bit of scrambling and nerve – kept the story alive. Standing at the entrance today, it's easy to see how the legend took hold. The mouth of the cave is small and unassuming, but once inside, it opens up just enough to stir the imagination. You don’t need to believe in sleeping kings to feel something powerful here. It’s a place of silence and shadow, where the air feels still and heavy with time.
Whether you view it as a sacred site, a geological curiosity, or a timeless story set in stone, Arthur’s Cave rewards those who seek it.
Glynneath Gunpowder Works:
Venture deeper into the wooded trails and the forest begins to change character. The path narrows, trees grow thicker, and then – almost hidden beneath the undergrowth – you begin to spot the moss-draped remains of stone buildings, water channels, and blast mounds. This is the haunting footprint of the Glynneath Gunpowder Works, the first gunpowder manufacturing site in Wales, established in 1857.
At a time when industrial South Wales was booming, there was high demand for explosives to drive the coal and metal mining that powered the region. Glynneath’s damp, wooded gorge offered ideal conditions: a reliable water source for power, thick forest cover for safety, and natural isolation from populated areas in case of accidental explosions. It was an environment tailor-made for volatile enterprise.
What began as a modest operation quickly grew. The site expanded into a sprawling complex of over 20 separate buildings, each carefully spaced apart to reduce the risk of chain-reaction blasts. These structures included mill houses, drying ovens, storage magazines, and mixing rooms – all connected by a complex network of tramways and leats (manmade water channels). The water of the River Mellte was harnessed to power huge waterwheels, which turned the crushing mills that ground charcoal, sulphur, and saltpetre into the essential black powder mixture.
The gunpowder produced here wasn’t just for local use. It was transported across South Wales to fuel mining operations, and even exported to other parts of the UK. At its peak, the works employed around 100 people, many of them local, and operated right through until the early 20th century. However, as dynamite and more advanced explosives became widespread, traditional black powder fell out of favour, and the site eventually closed for good in the 1930s.
Today, nature has reclaimed much of the area, but the bones of the gunpowder works remain surprisingly intact. As you wander through the trees, you can still spot the foundations of magazines and stone walls, now cloaked in ivy and fern. In some spots, you can even make out the gentle slope of tramlines, once used to shuttle barrels of powder between buildings. Interpretation panels along the way provide context, helping visitors imagine what it must have looked – and sounded – like when the works were alive with human effort and industrial roar.
It’s an eerie but fascinating place and this site is one of Wales’ most important preserved examples of 19th-century explosives production, and one of the few where so many original features remain visible in the landscape. It’s a must-visit for anyone with an interest in industrial heritage – or just a love for the way nature and history entwine in places like this.
Bwa Maen:
As you follow the Sychryd Gorge back down the mountain, it’s easy to get swept up in the waterfalls and woodland – but take a moment to look up at the cliffs across the river, and you’ll see something truly extraordinary: a dramatic ripple in the limestone wall known as Bwa Maen, which means "stone bow" in Welsh.
This isn’t just a curious rock formation – it’s a visible, powerful reminder of the earth’s deep-time drama. What you’re looking at is a geological fold, created hundreds of millions of years ago during the Variscan Orogeny, a mountain-building period when ancient continents collided. Under intense pressure, the layers of limestone and sandstone were buckled, folded, and deformed, and Bwa Maen is one of the clearest examples of that process in all of Wales.
The fold is shaped like a massive arch – like the earth has been softly pushed and crumpled like a carpet – and it's visible from the path opposite, where it seems to leap out from the forest like a frozen wave. It’s not just beautiful, it’s rare. This kind of exposed folding is more commonly found in alpine environments. To see it here in the Brecon Beacons is both surprising and humbling.
But these forces aren’t just ancient history. This part of Wales is still geologically active, and though we don’t often think of the UK as a place for earthquakes, South Wales has experienced its fair share of tremors. In 1906, an earthquake estimated at 5.2 magnitude shook the Swansea Valley – the strongest quake ever recorded in Wales. More recently, in February 2018, a 4.6 magnitude earthquake struck near Cwmllynfell, just a few miles south of Bwa Maen. It was felt as far away as Liverpool and Devon. While no major damage was reported, the event was a reminder that the bedrock beneath our feet is still shifting, still alive in geological terms.
It’s a spot that often gets missed by walkers rushing towards the waterfalls, but pause here and let it sink in. You’re looking at the folded bones of the earth, a place where you can see geology not just described, but dramatically exposed – raw and real.
Tips for Your Own Walk
Distance & Difficulty: This route is moderate – around 4–6km depending on detours. The main path is accessible, but Arthur’s Cave and Dinas Rock require sure footing.
Footwear: Sturdy walking boots are a must, especially after rain.
Best Time to Visit: Early morning or midweek for fewer crowds. Weekends can get very busy and parking can be difficult.
Safety Note: Don’t enter the mine – it’s unstable and dangerous. I visited with the mine owner.
Final Thoughts
This walk is more than just a ramble through pretty woods. It’s a journey through layers – of rock, of time, of human effort and myth. Pontneddfechan might be a quiet village, but it opens the door to a world that feels truly ancient and alive. If you’re looking to step off the beaten path and into a storybook of stone and water, this is the place. And I guarantee: once you’ve heard the Sychryd’s song and stood where miners, kings, and rivers once roamed – you’ll be back... probably more than once!
Watch the full Dinas Rock Vlog here:
Comentarios