Trips & Reports for Croesor Rhosydd (mine)

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Sunday July 18th 2010

Croesor Rhosydd (mine)

Toby, Simon, Sarah, Max, Matt, Mark, Laura, Gary, Debbie, Chuck

Matt wrote...

Report edited and updated following return trip in November 2011

Croesor Rhosydd - what an exciting adventure this was!

Sunday morning was not a pleasant one - heavy rain and winds pummelled the tent all night, and by morning, visibility was low and the weather was atrocious! This had not been forecasted and several people had consequently not packed as much waterproof stuff as maybe they would have liked! The drive to Croesor was equally wet with roads flooded and we were uncertain whether the water levels in the mine would have risen. One road into Croesor was blocked by flood waters.

We parked in Crosoer car park in heavy rain and got changed. Gary and I opted to walk up in boiler suit and waterproofs (after being very warm down the mine on our trip last year) while everyone else went with the full caving gear. Moral was a little low as we were pummelled by heavy rain as we changed and then walked up the hill. The walk up to Crosoer took about 45 minutes. I left my waterproofs in the entrance and opted to go through the mine with my undersuit, a thermal T-shirt and boiler suit, which subsequently proved to be fine, although full caving gear is also fine as you spend a lot of time just sitting around.

Following the entrance adit for several hundred metres reaches the first area of interest - an old brick built room in the corner of a wide open chamber. Further on, on the right hand side a short passage reached an enormous flooded chamber with a eerie lake of bottomless depths! Ignoring this and continuing ahead reaches a climb up a walled structure (with several in situ handlines) to the bottom of a long slope with a huge pipe down the left hand side. Following this uphill. several routes on the right lead to a drop into the previously seen massive cathedral. However, the way on is to follow the slope all the way to the top, where the first pitch is on the left.

The in-situ rope looked good, so we started down,using a system of light flashes to signify rope free (as a description we had advised against making sudden loud noises due to the unstable nature of this enormous chamber - car sized blocks of slate were poised to fall everywhere). I was last down the rope. About half way down the rope, I felt a sudden jolt, as a section of completely knackered rope, worn completely to the core, jammed between the rack bars. My heart rate shot up instantly, and still being 10+m from the ground I though the rope was about to snap and that I was a goner! Thankfully it held enough for me to force my rack past the narrowing in the rope where it was worn and I continued down past the dodgy section of rope very carefully. I was glad to reach the floor!

EDIT 2011: This rope is still dodgy, although the really worn section has been knotted out, requiring a knot pass manoeuver. Several new rope protectors have been added, plastic slabs bolted to the rock which makes the top half of the pitch more re-assuring. We recommend that any future trips rig your own 30m rope, which can be derigged by a couple of fast people running back in on the way back to the car later (you walk back via the Croesor entrance). Unfortunately the bolts are not well placed to allow for a pull-through.

A 150m scramble across the slate-strewn enormous chamber reaches a slope descending through a huge archway on the right hand side, the head of the second pitch. We knew the rope had recently been replaced here so were more confident in using it. EDIT 2011: This rope is still in good condition and several new rope protectors (more plastic slabs bolted to the wall) making this pitch much more reassuring.

Glad to be at the floor, the zip wire is reached only 30m downhill. Most people were already across by the time I arrived. The trip across the zip wire was tremendous fun, and uses a Petzl steel double-pulley (as metal wires shred alloy ones). The pulley is attached to the wire, and some string, cord, or even better, a fishing reel is attached which can be paid-out quickly as the person zips across, to allow for the pulley to be pulled back. It is important to weight the pulley with a few steel krabs or it flips up and gets stuck when trying to pull it back unloaded. An in-site rope provides a backup.

Beyond here a short boat trip across a flooded section (formerly the suspension bridge) (EDIT 2011: The bridge has now been raised and a boat is no longer required here).

Following the obvious stomping route on from here reaches after several minutes (passing through several chambers) the first of three bridges. This first bridge is the easiest as it has a wooden strut all the way across it, which can be traversed while clipped into an in-situ safety line. The second bridge has absolutely nothing to walk across at all and is consequently passed by using the pulley to zip across a wire line. (EDIT 2011: The second bridge has been completely re-rigged as a traverse around the right hand side of the water with rope and a metal wire to clip into. The second section of this is quite strenuous and is pretty much a hanging travese and requires hauling yourself on the metal wire so make sure you have good gloves).

The third bridge, the Bridge of Death is soon reached. Since our last visit, a section of railway track has been retrieved and suspended across the first half of the bridge, supported in the middle by rope to prevent too much bend. This can be traversed along, clipped into a rope as backup (although this was out of reach by the middle of the bridge, and so we put a sling on a steel Krab onto the wire to enable clipping into the sling hanging down rather than the wire itself). The second section of the bridge has nothing to stand on and must be done on the pulley and wire, again with a sling between the pulley and yourself because the wire is so high up and out of reach for most people. The pulley may be returned by simply flinging it back along the wire. (EDIT 2011: Not much change, though I think the middle bit of the bridge has been re-rigged slightly to make it easier and not quite as high). Crossing the Bridge of Death is a heart pounding experience!

Immediately beyond the Bridge of Death, the main lake is reached, where one must abseil 5m down a fixed rope into a waiting inflatable boat on a huge bottomless lake of pale blue water. The lake is approximately 30m long, and the boats are pulled from one side to another by an ingeneous system, by which some thick polyprop cord runs a full loop from the top of the rope, down to the water level and across the water and then back to the top of the rope. We found no boats waiting for us, however, on pulling on the cord, two in-situ boats appeared out of the darkness. We inflated Stingray II to create a third boat and attached it to the floatilla. Groups of three took it in turns to abseil into a boat, before being slowly pulled across the lake to a small slate beach at the other side. Once across, a short prussik up a fixed rope regains the main passage. (EDIT 2011 not much change here, pulleys have been added to make the system more efficient, and a floating raft at the bottom of the rope allows easier access into the boat. No in-situ inflatables, but a full size canadian canoe was found which required emptying of water before use).

Continuing along the main passage at the top of the rope passes two loose slopes up on the right hand side. Taking the second one is the way on (not sure where the first goes) and at the top soon reaches a wall where you cross over into Rhosydd mine. Following straight on through several big chambers reaches a slate collapse in the main onward passage, which must be carefully negotiated to pop out into a huge chamber with daylight/moonlight visable from above.

Five minutes of scrambling up the chamber towards the light reaches the huge and spectacular gaping mouth of Rhosydd mine and the pouring rain again. It was dreadful weather, with no more than 15m visibility and pouring rain. Water cascaded down every possible surface!

Getting out of the deep depression at the entrance to the mine is surprisingly tricky, especially as you assume that the adventure is now over. The mine entrance is on a shelf, approximately 6-7m below the main level of the surface, with few places where you can climb up. We found this difficult last time when it wasn't even raining and slippy. Si decided to attempt a grassy slope on the right approximately 30m beyond the mouth of the mine, which he successfully negotiated, while I carried on round the side of the 'shakehole' (with a steep drop on the left) for approximately 200m until a difficult (and very exposed) climb up a loose rock face enables an escape from the depression. I returned to the top of the slope to meet Si, and we threw a rope down to assist everyone else out (EDIT 2011: Once again, extremely difficult, the rock face 200m around the right hand edge of the depression proved the best route of escape).

All I can say next is thank goodness we had taken a GPS fix at the Croesor entrance! With almost no visibility and torrential rain we wouldn't have had a hope in hells chance of finding our way back to the Croesor entrance (or the car) across the barren featureless moorland. However, the GPS prevailed and within 20 minutes of squelching the slate tower at Crosoer mine entrance loomed out of the mist and we were back at Croesor entrance to retrieve our gear. We were soaking wet but thoroughly high spirited after such a truely superb adventure.

Essential equipment for the trip includes

(A) Steel double pulley.

(B) Selection of steel karabiners (to clip into metal wires, and to weight the pulley to prevent it flipping upside down when nobody is on it).

(C) Selection of slings.

(D) 40m of cord, string or fishing line on some kind of reel for very quick reeling out on the zip wire (this needs to automatically reel off so the person holding it doesn't get their hand ripped off when someone launches themselves across the zip wire).

(E) 35m rope and some krabs/maillions to rig the first pitch. 2011: In situ rope on first pitch is very dodge, but new rope protectors are good.

(F) Another 30m rope for other uses (emergency and also to escape the depression of Rhosydd mine if necessary).

(G) Inflatable boat with pump.

(H) GPS to fix the Croesor entrance - ESSENTIAL if you want to find your way home from Rhosydd!

(I) Gloves for everyone (metal splinters from wire ropes)


Simplified walkthrough:

(A) From the entrance adit follow obvious route then climb up the walled structure and to the top of the long steep slope.

(B) First pitch at top of slope on the left (30m rope needed, in situ rope is extremely dangerous).

(C) Scramble through huge chamber to second pitch under huge archway on right (in situ rope seems sound).

(D) Zip wire is immediately reached 30m from bottom of second pitch.

(E) 10m Lake is immediately reached (boat required) EDIT 2011: Boat no longer required as bridge has been raised.

(F) Follow obvious stomping mine tunnel for several minutes (via several very large chambers) to first bridge, easy traverse.

(G) Next bridge soon after 2011: Now a hanging traverse.

(H) Bridge of death is then reaches, combination of a travese and a steel wire with pulley.

(I) Final lake is immediately reached after Bridge of Death (abseil into inflatable boats/canoe and pull yourself across).

(J) Prussik up 5m in-situ rope beyond lake.

(K) Ascend the SECOND steep sloping passage on right.

(L) Follow main route past several large chambers.

(M) Crawl through a slate block collapse in the main passage (the only unobvious bit or routefinding) into final huge chamber.

(N) Ascend huge chamber towards daylight.

(O) Follow around the right hand edge of the depression for about 200m to reach a steep rock face that can be climbed to escape the depression.

(P) Turn on GPS to find you way back to the Croesor entrance.

21st July 2010

Matt Ewles

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36 photos by Chuck...

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Saturday May 23rd 2009

Croesor Rhosydd (mine)

Gary, Matt, Ade, Laura, Tash

Gary wrote...

I would defiantly say that Crosoer Rhosydd mine is the most fun you can have underground! It's like the ultimate cavers adventure playground! Crosoer Rhosydd has some of the most fun (and at times terrifying) wire traverses I've ever seen.

After a long walk up the hill overlooking spectacular landscape, we were greeted with the prominent winding house and steep track-way leading down into the bottom of the valley. The large flat plateau around the winding house is littered with old mining history – twisted wire and buildings in various states of decay. At one end of a row of these structures is the remains of a water wheel, and just behind is the entrance to Crosoer mine. The actual entrance has long since been closed off behind a steel door and tons of rubble, however the way in is through a grill on the left.

The classic adit entrance is fairly un-inspiring until, after a short walk, we entered a large area with several ways on and a very deep hole, filled with water in the middle of the floor. To the right leads to probably one of the eeriest places I ever been in; a huge excavated hall towering up for at lease thirty meters, with slanted rock lined with blast holes. Below, the floor descends downwards and is filled up to the floor of the entrance with water – deathly still and totally silent. It’s possible to drop a rock into the water and watch as it drops for some distance until disappears out of site in the clear blue water.

Leaving the flooded hall, the way on was up a slope following a large pipe, passing a window overlooking the first hall from a higher level. The slope ends at the head of pitch overlooking another huge hall, again totally silent. Matt, Ade, Laura and Tash went down the fixed rope one by one while I set up my camera to catch the descent. I followed last and dropped into one of the biggest caverns I’ve ever been in, stroon with huge, bus sized boulders. We had been told that rocks fall out of the roof regularly and its best not to make much noise (not sure how true that is!) Not wishing to tempt fate, we preceded in silence (unusual for cavers) through the bouders to another, longer descent was made by some rope of dubious vintage running via some home made rope protectors over a ledge and down to a smaller chamber.

Next came the first of many wire zip lines. Ade had purchased a steel pulley especially for the occasion (defiantly a must as the wire will shred the cheaper alloy ones). After some debate about how best to cross the wire over the deep water we decided to just clip in and jump! Thankfully we’d remembered some cord to pull the pulley back after each trip over. After taking some photos, I clipped on and leaped off the ledge. The wire is quite steep and I didn’t expect how fast I’d be moving. The wall on the other side appeared out of the darkness so I just stuck out my legs, closed my eyes and braced for impact. The resulting ungraceful thud shuck my bones but wasn’t too bad - just make sure you’re not going head first!

After everyone made it across, it was time to blow up our £5.99 inflatable dingy. It turned out that we didn’t really need it as there were several already there, all be it half were flat or on the bottom. As Tash had here head inside our dingy puffing away as hard as possible, we heard voices from behind - another group of cavers were catching us up. We picked up the pace and made the relatively short voyage over the lake and the dingy was deflated – I think bringing ores (much to the entertainment of the other group) was rather over the top.

Onwards through more large mine passage to the next zip wire and one of several crossings over flooded passages below. As we crossed each of the similar obstacles, the remains of the bridges were getting increasingly less and less until the last one – “the bridge of death” – where only a bendy old iron rail was there for the foothold. To add to this, the zip wire was re-belayed half way which made for some interesting discussion on how to get the pulley back for the next person. In the end we managed to cobble together and improvised system using some steel krabs – a bit crude but it got us all over (not helped by the comments from the group behind us, waiting to cross).

Out came the dingy again. This time we had to abseil into it! Ade took the first journey and I went next. The way on is to cross a large stretch of flooded passage – easily twenty meters wide and thirty meters long. Once again, ores weren’t required as an ingenious hauling pulley system had been erected to pull our rather unstable vessel along and then return it for the next passenger. This area we named the boat graveyard as it was littered with all manor of rather un-seaworthy dingys – some even could be seen on the bottom or caught on rocks. We utilised one of the other dingys for Matt, Laura and Tash to make the crossing quicker.

After debarking and making the short climb up to the continuation of the level, it was easy going. We went through the connection with Rhosydd mine and passed some rather impressive workings to the climb up to the exit.

The exit was far bigger than I expected – a huge hole at the head of a steep boulder slope with sunlight streaming in – quite spectacular. Getting out of the mine was easy, however getting out of the shake hole was rather more of a challenge! After Laura made a rather dangerous attempt at climbing up a wet slope, we all made it up to the moor top to find we were in thick fog. Time for the GPS we thought, and a good thing we had it too. We found our way back to Crosoer without too much difficulty (apart from Laura who fell up to her middle in a bog) and made our way down, below the fog to the village.

An excellent and very satisfying through trip, making a nice change from our usual dales caving. I would defiantly recommend visiting this mine soon as it probably won’t be passable for much longer due to the sate of decay of some of the features.

24th August 2009

Gary Douthwaite

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Tash wrote...

<i>The first official club weekend away in an unbelievably sunny Wales. No, you didn’t read that wrongly – it was a sunny weekend in Wales!</i>


The highlight for me was the Crosoer Rhosydd through trip . A colleague had recommended this trip to me a year or so back and I’ve been itching to do it since. How could you not get excited about a trip which needs a boat?! It was a fair drive from our campsite in Langollen but worth it.

We parked up in the village and got some very odd looks as we sorted rope, boats, oars and pulleys as families and walkers donned their walking boots for a pleasant summer stroll.

A slog up an old mine track (if only the railway was still running) led us to the old mine workings and the start of Cresoer Mine. This has been empty since the 70s but already dereliction was setting in – in fact the entire mine is in an active state of collapse.

The first section was really eerie, as we walked passed the deserted office and flooded chambers. The water is completely still and incredibly dark. As we gained height and viewed the chambers from the upper levels, you began to appreciate the scale of the mine – my puny light barely reached the walls.

A short abseil on in situ gear led us into chamber one, which was awe inspiring in its scale. However the scale of the chamber also meant the roof was struggling to be supported and there were house sized boulders strewn over the floor – not a place to hang around! We had also read that simply shouting was enough to trigger collapse here so we tiptoed across (as delicately as you can across loose boulders!) in silence. I’m sure the shouting theory has got to be myth but I sure as hell didn’t want to be the one to disprove it! I’ve never caved in silence before and it’s very very odd, and what was more disconcerting was that I still had the remnants of a cold and desperately need to cough!

Thankfully we all made it through intact and after another abseil on in situ gear (and rope protectors in a variety of states!) we arrived at the first water crossing – Tyrolean time! It was then time to unfurl the mighty Stingray – our trusty vessel for the second water crossing (Stingray is a dingy of Matt’s bought 10 years ago and never used). It was short crossing, but stingray performed impeccably and no one got wet.

A series of bridges were next, although that term should be used fairly loosely! I crossed the rotting wooden beam first. It should have been easy: I was sober, I generally have no problems walking in straight line, but there is something fairly unnerving about walking across a plank over a large drop into very deep water and not wanting to endure the humiliation of falling.

The much hyped “Bridge of Death” turned out to be more of a tightrope / zip wire of death. With some cunning systems involving string to share steel krabs / pulleys (despite having about 50 pulleys between us we were trying to conserve our gear from the aluminium eating steel cable - take the cavers out of Yorkshire and all that…!) we crossed successfully. Short people beware though, unless you are happy pulling up on rusty struts then you will get strung up!

The final water crossing was my highlight, you had to abseil into the dingy!! Stingray, along with another in situ vessel, again served us well (although there was a distinct sound of hissing) and it was a short distance to the Rhosydd mine connection and the daylight streaming in down the huge boulder slope that marked our exit.

In true Wales fashion, the cloud had set in and visibility was poor on our exit. We were very glad of our GPS in finding our way back to the miner’s path (although this didn’t stop Laura disappearing waist deep into bog at one point!).

All in all this was a really fun trip and I particularly enjoyed the novelty of the water crossings. Also glad we did it before everything disintegrates or the mines collapse completely!

For me the rest of weekend was spent working / reading / sunbathing / wandering – it seemed rude not to enjoy the glorious weather. The rest of the group enjoyed a trip down ODB on Sunday and showed off their digging skills! So an excellent weekend: good trips, nice campsite and stunning scenery.

14th June 2009

Tash Durham

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Laura wrote...

This was a fantastic trip, definitely one of my favourite this year. I woudl definitely reccomend it to anybody visiting the area. The mine is like an underground adventure playground with zip-wires, lakes to cross in an inflatable boat and the bridge of death. We followed the description written by Richard Gover from YUCPC a couple of months previously, which was spot-on. The mine is definitely in an active state of collapse; some parts of the bridge of death has collapsed since Gover's trip! Definitely take a map and compass or GPS for the return journey overland as it isn't simple to find the way back and I ended up waist-deep in a bog!

23rd September 2009

Laura Bennett

48 photos by Gary...

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