White Powder Everywhere

Team: Paul Crowsley, Si Lowis, Lesley Markie, John Roe, Samsung S7, Claire Vivian, Neil Weymouth, Tarquin Wilton-Jones.

Report and photos: Tarquin Wilton-Jones.


This was a very welcome chance to visit one of my favourite caves with some SWCC friends, and at the same time look for some newly recognised formations. The weekend had been booked long in advance by the ever-organised club meets secretary. Sadly the weather could not be booked in advance, and some snow had decided to coat the hills. Certainly beautiful, but the single track lane to the Llangattwg caves has no chance of being cleared by the council. Having grown up in these hills, snow is just a fact of life and quite fun to drive in, but several members of the teams were forced to pull out of the trip after reports of crashes blocking major roads on the Friday evening.

Still, 7 of us had braved the roads, 6 arriving on Friday, and me joining on Saturday. One had tried and failed to ascend the treacherously steep roads up from Crickhowell, but all of us eventually used the Hafod road, that runs level all the way around the mountain from Brynmawr along a former tramroad. At one point, it runs above 70 metres of slope and cliff dropping down to the Blackrock road below, with only a few little wooden posts offering very little psychological support. The view, however, is stupendous. By Saturday morning, the compacted snow had earned an icy crust, and the final section towards the Whitewalls caving hut added a little extra excitement with no grip whatsoever for a short section, where drops on both sides offered an alternative to the road as the car pretended not to understand the commands being sent by the steering wheel.

The plan was to spend two days at Whitewalls, visiting Agen Allwedd - Aggy - on Saturday, and other local caves on Sunday. The seven split into teams of four and three, visiting the Aggy Inner and Outer Circles, and The Courtesan plus Grand Circle respectively. Panoramas and Circles pictures by Tarquin, unless otherwise stated, lighting of big passages by everyone on the trip.

Si, Paul, Leslie and Tarquin

Aggy Inner and Outer Circles

Team: Tarquin Wilton-Jones, Claire Vivian, John Roe, Si Lowis

The Black Mountains from the Tramroad

Cwm Onneu Fach and the Llangattock Escarpment

This is one of the Aggy classics, taking in most of the largest passages in the system, excellent streamways, a great many grand old stal formations, a very committing tight squeeze, and one of the cave's lengthy workout passages. The 2 km walk to the cave is one of the most scenic in the national park, with a dramatic escarpment on one side, and a view over the Black Mountains ridges on the other. In conditions like this some decades before, a former clubmate of mine had accidentally tested the steepness of the slope below the tramroad, and somehow survived without any significant injury despite a very rapid trip to the trees 50 metres below.

The familiar Entrance Series is one of the best places in the UK to see lesser horseshoe bats, which adorned the walls at almost every turn. This was particularly special for Si, who had never seen so many in one place before. The junctions quickly passed, go right out, or get left in. First Choke then reached Baron's Chamber, and the splendour of the enormous Main Passage.

John, Si and Claire in Main Passage

This is where the hunt for white powder began, but sadly the only powder was the prevalent piles of spent carbide, a relic of the lack of conservation of past eras. Thankfully, carbide and its soot marks and waste piles are now banned from these caves, but the past damage still remains, and it made it much harder to search for a white powder, among the white powder.

Main Stream Passage's mix of splashing and boulder hopping provided some entertainment, and after a couple of false starts with photography of what is almost certainly just carbide (doh!), we reached the Second Boulder Choke. If you manage to spot them, there are even a few proto-shark fossil spines here, similar to those in Draenen. A short choke then a distinctive climb down into a side passage, followed by another climb down and return to the Main Stream passage, reached the grovel in the stream below the longer part of the choke. A climb up boulders then reached Keyhole Passage, my personal favourite (so why is there no photo?!), a perfect phreatic tube with a deep vadose trench meandering in the floor. We took the upper route, crossing the deep rift repeatedly on the ledges, and then dropping down the climbs to the stream at the far end.

The streamway then lost its boulders, and the increasingly slippery floor brought us to Northwest Junction. From here, we headed upstream along the longest uninterrupted streamway in Britain, Turkey Streamway, named after a rather odd shaped stalactite. The occasional formations began at The Beehive, which serve mainly as a reminder that Aggy does in fact have formations. Somewhere. The streamway is excellent, and overshadows the stal, though the stal is in fact quite attractive in its own right. Just before Turkey Pool, a small pile of crystals looked suspiciously like the white powder I had been looking for, but sadly is probably something else entirely, due to the proximity to the stream.

The deep pool appears at first to be a sump, but a rift tucked to the left is the way on. A fun obstacle, narrow and with few holds above the chest deep water, but it is possible to get through with dry feet if you traverse well. Most of us managed, with only the odd wet foot (Claire managed to get one wet foot). The brief enormity of Turkey Chamber gave a hint of the grandure yet to come.

Claire crossing Turkey Pool on an earlier trip (using the same foothold and getting the same foot wet) Photos: Andy Freem

A short section of streamway, and we took a small side passage into the very impressive Sand Caverns, where we stopped for the first passage photo. This passage is so much bigger than it feels like it should be, a remnant of a much older drainage system. The end of Sand Caverns was as far as Claire had been in Aggy, and it is always nice to have someone enjoying a first visit to the rest of the area, since it is very dramatic indeed.

Claire and John in Sand Caverns

John, Claire and Si in Sand Caverns

Cross section through fossilised Brain Coral

 From Sand Caverns, we took the crawling-sized Selenite Needle Passage instead, with the walls soon becoming decorated with small amounts of selenite, and occasional poor helictites. The main feature, however, is the Nodular Bed that makes up the roof. Initially seeming just like limestone rocks embedded in shale, a recent visit brought the revalation that the rocks are almost certainly fossilised brain corals. Some of them are preserved well enough to see the characteristic surface texture of the corals, with the bright purple shale filling the gaps between them. In many cases, the coral has been cut open by the cave, leaving a visible cross section with large crystal rays extending outwards - the growth pattern of the coral.

At the end of the passage, the walls are decorated with extremely elaborate, pure white growths. Here, the stream is gained, and a second inlet then signifies the start of the Inner Circle. The survey of this area rather appropriately looks distinctively like a simple drawing of a turkey; the body is the Inner Circle, Midsummer Passage and Swiss Passage are the tail feathers, Selenite Needle Passage and an inlet are the legs, Disappointment Chamber and a side passage are the bottom and top of the head. We continued along Eastern Avenue, following the Inner Circle anti-clockwise, since this gets the most dramatic reveals of the passages. At Midsummer Passage, we turned left, to reach the junction with Swiss Passage.

Swiss Passage is always worth a visit, to admire the beautiful mud formations. First are the dried crystal pools hiding in the undercuts, surrounded by the untouched mud. After that is the iconic Swiss Village, a series of miniature hoodoos formed by water dripping onto the mud, with each pinnacle protected from the water by a tiny pebble.

Swiss Village

After Swiss Passage, we headed in the other direction along Scree Passage. The first and most obvious obstacle is the First Scree Slope, a steep slope of scree (in case the name didn't give it away), and the team very kindly took their places at various stages up the very awkward slope, for a picture. At the top is a distinctive chamber, with a ceiling adorned with immature helictites, and a natural dry-stone-wall of boulders that have peeled away from the roof.

Si, Claire and John on the First Scree Slope

John and Claire above the First Scree Slope

 After a great deal of searching throughout the trip, my persistance finally paid off. Scree Passage presented some white powder, that was not just another scattering of spent carbide. This was clearly going to be cryostal, exactly where I had hoped to find it. My shout of "Eureka!" was no doubt rather comical considering how meagre the dusting was, and how willing everyone else was to just walk past it. "All that excitement for that?!" "I have to admit, I wouldn't even have noticed that, I would have just stood on it." were comments heard. And this is why it has only recently been recognised.

Cryostal in Scree Passage

The Second Scree Slope once again presented another photographic opportunity, and the rest of the team kindly obliged, dodging the rocks dislodged by those further up the slope. The Dome of Saint Paul's at the top is very hard to capture without a very wide angle lens. The chamber is almost perfectly circular, with layers of shale and thin limestone making up the walls, and an extremely flat ceiling. It is also quite far above, so lighting it proved a little too challenging for the camera. Oh yes, the camera. It's not a camera, it's a phone. All of the pictures are taken with a phone. Because everyone wants to take a delicate touchscreen worth several hundred pounds underground, to take pictures of white powder, right?

Claire, John and Si on the Second Scree Slope.

The descent into Saint Paul's Passage is one of the most dramatic in the cave, and the passage is simply enormous, rivalling the giant passages of Daren Cilau and Draenen. In the floor, I managed to find another set of probable cryostal looking like gold nuggets, while the rest of the team tried to decide if a side passage was the way on (the turkey's head). The rest of the Inner Circle passed fairly quickly, with a short low crawl regaining the brief large chamber and passage, before rejoining Eastern Avenue to close the Inner Circle loop.

Once again we followed Eastern Avenue, this time turning right at Midsummer Passage. This really looks big on the survey, and it certainly starts so, but it quickly chokes. A crawling-sized route beside the choke regains the larger passage. From here on, the survey is a little optimistic, showing a large passage. It certainly is wide in places, but it is very low, requiring two flat-out crawls and a lot of stooping. Just as the passage regained its former grand size, we instead located a silly hole dropping down behind a large boulder. This is the top of the infamous squeeze. 7 years ago, this was the squeeze where I finally lost my caving nerve, with flashbacks of a recent epic in Draenen. However, in 2017 I had passed it and proved that although it may feel intimidating, it is a lot easier than it appears at first. On that occasion, the great Clive Westlake had patiently tested the squeeze and led the rest of us through once he found the tactic that worked.

The hole descends diagonally to a very narrow rift, where rather than descending the obvious but impossibly tight slot below, you have to squeeze horizontally over a rock, keeping your body high in the widest section. At the next slot down, turn so that your feet point downwards, then descend to emerge from a seemingly impossible position in the roof of a passage. From above it looks insane. From below it looks like a piece of paper would struggle to fit through it. In the past, I would send a smaller caver through first then drop head first since it is easier - but horrifyingly committing - that way. This time, I was the first through, and it all simply worked, feet first.

Si committing to the horizontal section of the squeeze

 Si spent some time trying to work out how to get his chest through the tightest section, and no amount of guidance can make your chest smaller - let's face it, there was no guidance anyway, since I was preoccupied with videoing it. After nearly having to abandon the attempt, Si finally found the solution, forced himself through with a bruise for his trouble, and emerged from the slot with a well earned sigh of relief. Claire soon followed, backed up with Si's guidance. John seemed to take it in his stride, and soon joined us, saying that he was more familiar with tackling the squeeze upwards, since at least you can more easily back out if you fail to get through, but that also means far more cavers fail to get through, since gravity is working against them. Having backed out once while descending into the squeeze, I can say that it certainly is possible to re-ascend if you decide not to go through after all. On the way down, one tactic is to put all of your valuables, especially your car keys, into a bag and drop them down the hole first - then you are forced to complete it in order to retrieve them. No backing out.

Claire squeezing in to Coal Cellar Passage with Si's guidance

The hard work had begun. Coal Cellar Passage is about 0.5 km long, and very sporting. For a long way, there are few places where you can stand, with awkward crawls and thrutches over rocks. At one point, the passage appears to close down completely, and an earlier crawl in an undercut is needed to regain the way on. Further on, sideways walking becomes possible as the passage becomes a very narrow rift. It is rare to be able to turn around, so one leg ends up doing most of the work. In many places, it was impossible to turn your head to check on the cavers behind you, so we had to rely on the "you still with me?" checks. Sideways squeezing is sometimes the only way to make progress. Occasional jammed rocks and one memorable calcite obstruction force climbs up the slippery rift without holds of any kind, with Claire's petite stature needing a carefully placed sacrificial caver as a foothold. An inlet finally increased the passage dimensions so that regular walking became possible, at least for some of it.

Now well muddied, we reached Turkey Junction, and the Outer Circle was complete. The return journey was quite methodical, back through the familiar passages. The climb up into Keyhole Passage and the climb up between the sections of Second Boulder Choke being perhaps the only places which presented a significant challenge. We stopped to photograph Main Passage, then Si tested his memory by leading out through the entrance series. Go right out, or get left in. Over to the right. Further right. The entrance to First Boulder Choke is definitely confusing.

The Entrance Series was over pretty quickly, and we soon passed the large collection of peppered moths, herald moths and cave spiders to emerge onto the snow-covered tramway. "White powder? Whatever you do, don't look down." A speedy trip, 6 hrs 45 minutes. A frosty walk back, where Claire decided not to race through Eglwys Faen - next time, maybe - and the white-roofed Whitewalls appeared as a welcome sight. Hot showers, a gratefully received cup of tea, chocolate biscuits, and even the offer of pizza! Sadly, our hopes of a curry in Crickhowell had been dashed by the ice on the steep Crickhowell road.

While waiting for the other team to complete their unexpectedly long Courtesan trip, we checked the mountain weather forecast, and it had become much worse. Icy temperatures, blizard conditions, gale force winds, sleet causing rapid snowmelt and flash flooding, then more snow. None of us wanted to risk caving or driving the next day, so we decided to back out early and head home. The road back was safer with the ice melting, but would be absolutely treacherous the next morning. By Sunday, most of the Valleys were thickly covered in snow, and more was arriving. A good decision.
As always, I would like to thank my team mates for the excellent company and patient photographic modelling during the trip, and especially to Claire for making all the arrangements. Even if you couldn't arrange the weather.

Aggy Courtesan and Grand Circle

Team: Paul Crowley, Leslie Markie and Neil Weymouth.

This was originally proposed as a Courtesan trip, but by the time the logbook got filled in, it had become a Grand Circle trip too, presumably to avoid having to do Southern Stream Passage twice.
Up to Main Passage, the trip is the same as the Circles trip. From there, it stays with the Main Passage for longer, mostly walking along a large, mud-floored phreatic tube. At the giant portals of Southern Stream Passage, the large passage with selenite-covered walls is short-lived, and a hole down in the floor is the start of the real Southern Stream. At first, it is possible to walk for about 500 metres, but after first and second inlets, it lowers to stooping height, with several crawls forced by boulders. This gruelling section lasts for 600 metres, ending at a climb down at Waterfall Chamber. The walking sized passage returns, until a larger tube in the roof signifies Gothic Passage.

Climbing into Gothic, a crawl leads to the choice between the Priory Road and Maytime routes. Priory Road starts small but soon enters a much wider passage. The Iles Inlet side passage then reaches The Courtesan, one of South Wales' finest helictite formations, described as "much larger than you expect it to be".

The Courtesan (photographed on a previous trip). Photo: Duncan Hornby

Returning to Southern Stream Passage, the tall rift passage continues a great deal further, eventually forcing a traverse on slippery ledges, to reach the wide river of Lower Main Stream Passage. The pools here force a 50% soaking, as you try to make your way upstream. The biggest challenge, however, is the floor, which can be incredibly slippery, depending on the season, sometimes as bad as ice. The passage is enormous, but you spend so much effort concentrating on staying on your feet that it is hard to appreciate the space above you. Two tricky cascades which often result in a complete soaking then precede the abrupt Fifth Choke.

A climb up a knotted rope leads high into the roof, into Biza Passage, and a complete change in character. A phreatic tube with heavy scalloping, and an occasional vadose trench, normally walking or crawling sized, with a couple of climbs. Finally, a lengthy descent through the substantial Fourth Choke regains the dark and muddy Main Stream Passage. This soon leads to Third Choke, where the way on is not at all obvious, starting by dropping down on the right into the stream, and randomly heading through the choke without any solid walls, roof or floor. It emerges in another muddy part of the stream, the end of the longest uninterrupted streamway (combined with Turkey Streamway).

The Narrows usually require a chest-deep dunking at each end. It is possible to traverse most of the narrow section either fully out of the water, or at various levels partly in the water. It is deep enough to be completely submerged if you lose your grip. Pools called Deep Water can be passed with care with only a waist-deep wade. The slippery floor soon returns, for a very long way until Cascade Inlet, where the floor suddenly becomes quite grippy at last. A short distance on, and it reaches Northwest Junction, where the way out matches the Circles route.

10 hrs 45 mins, arriving back substantially before the callout time. All's good.