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NGR SO 5527 9923 A 215m VR 71m Horizontal Length 4km Surveyed Length 4.5km

Version: 0.01
Date: 29th November, 2005
Author: Jan Karvik

Miss Graces lane is a turning off the B4228 road, approximately 5 km each way between Chepstow and St Briavels, 700m up the lane on the left there is space to park a couple of cars. Only 20m east of the lane and 50m south of the foot path to the Devil's Pulpit, in a depression in the woods is the concrete entrance shaft, capped by a concrete block upstand and a locked steel lid.

Digging in the depression commenced in 1994 using the latest technology, an 18 ton tracked Proclian excavator, which removed boulder clay to a depth of 5.9m. A small concrete footing was cast to support 1.23m of 1050mm diameter concrete manhole pipes, followed by 4.52m of 740mm diameter sewer pipes.

For the next three years it was a question of digging down about 600mm at a time, through clay and boulders on Wednesday evenings. Typically a weekend day was used to complete the digging, then reusable shuttering units were installed, and the working face was secured by pouring in a ring of concrete. After 34 castings and approximately 40 tons of concrete later, in December 1997, at a depth of 28.5m, a breakthrough was made into Autumn Frenzy Chamber, 25m long and 10m wide.

At the northern end of this chamber, an inclined shaft was secured with scaffolding to a landing, where a vertical shaft was dug through wet clay and rocks, which was shored with scaffolding and stone walling. Fortunately there was plenty of space for all the spoil to be dumped in the Autumn Frenzy Chamber.

After nearly two years further effort the shaft opened into a rift at a level 30m below the entrance chamber. A 15m section of phreatic passage was explored to a choke, but it was felt that the continuing rift accounted for most of the draft. In December 1999, after extensively digging out and widening the rift the breakthrough into Winter Storm was made, a surprisingly complex series of passages and rifts formed on four different levels. Exploration and surveying gave a total horizontal passage length of 340m, despite the many promising leads several digging efforts added little extra, and when the foot-and-mouth disease hit in 2001, the projects were moth balled as the diggers focused their efforts on Kelly's Lane.

In March 2003 an investment in a "Testo" air velocity meter was made, in an effort to evaluate the different drafts at the various possible dig sites. One test was made in the choke at the end of the original 15m section of phreatic passage, where traditional methods of testing such as candles and smoke pellets had proved inconclusive. The meter however showed a very small reading a floor level, and a fairly consistent 0.35m/s to the right of a large rock choking the head of the passage. A return was soon made armed with auto rotating hammer and chemicals, and the rock was history. Further digging and long range aerial poking, soon gave access to the spacious passages and chambers of Spring Fever, raising the cave length to 1.7 km. In October 2003 a climb at the northern end gave access to the Canyon Series, and the cave spread it's matrix NNE once more. Presently the total horizontal cave length is 4 km, packed on various levels within an area 372m by 297m by 71m, on plan there is only 420m entrance to end and 475m end to end, however underground there are many times more meters to indulge in.

Description by Jan Karvik

[Provided is a comprehensive description of the original Winter Storm series, but for clarity and conciseness only the more significant routes within Spring Frenzy and the Canyon Series are described.]

The vertical 28.5m fixed steel ladder of the entrance shaft is descended to a landing, from which the remaining slightly staggered 2.7m of the concrete shaft may be easily free climbed. BEWARE after 6m the first ladder finishes in thin air, so it is necessary to stop and make an easy side step to continue the descent on one continuous length of ladder.

The shaft exits into AUTUMN FRENZY CHAMBER, to the right (south) various squirming routes through rocks and mud may be followed to disappointing ends at differing lengths and depths. Walking off to the left (north) leads to the end of the chamber, the scaffolded incline and the west wall of the chamber that heads back southwards, deteriorating into more squirming routes.

Descend the scaffolded incline to a landing, followed by a 12m fixed steel ladder down a scaffolded shaft to a 2m section of rift. To access the main cave, namely Spring Fever and the Canyon Series it is necessary to side-step left off the next ladder just 2m down, into the 15m section of phreatic passage heading NE. Ignoring this passage and continuing down to the base of the blasted out rift, leads NW through the December 1999 "Millennium Breakthrough Point" and up past some scaffolding shoring into the main Winter Storm passage heading S.


Up on the right side is an open area of large and threateningly hanging collapsed boulders. No leads on have been found here so a wide-birth on the left is recommended. This leads to the cross junction of the Tall Rift, the main passage now diminished continues S for 20m before choking up. Leaving only a blasted passage rising on the right heading NW, briefly looking promising, but splits up into drafting but diminishing crawls and fissures.

The main route on is traversing SE along the Tall Rift. [Routes down to the floor, 11.3m below may be found and followed until it becomes too tight, it is also possible to climb up 6m and follow the breccia roof of the rift which widens to 1.5m]. The traversing ends after 10m at a cross junction, to the left leads to some short crawls, a dripping shaft and rift with a small stream at it's base. To the right is a small loop linking back to the main passage. Moving on along the Tall Rift requires a short climb down to a wider section, (watch out for this climb on the way out, it's all to easy to end up struggling along at too lower level). [In the floor of this wider section it is possible to squeeze down through boulders to view a small stream in the narrow rifts below, but it is loose and not recommended]. At the end of the Tall Rift the short section of passage on the left ends almost 30m directly below the base of the concrete entrance shaft. [Dropping tightly down 5m leads to a 5m crawling passage continuing E, and is the deepest recorded point in the cave]. The main way on up into the Multi Level Series is through the scaffolded choke on the right.

The scaffolded choke terminates in Multi Level 3, to visit the top and widest level, Multi Level 4, continue S for 6m to the second pile of fallen blocks and moving over them carefully climb up through the hole. The roof of Multi Level 4 is breccia, consisting of red and pink iron stained limestone lumps in a crystalline calcite matrix. Exploring the level one will find a passage containing displays of dog tooth spar calcite crystals, a wide area of breakdown and a sporting tube heading S, happily with ample turning space towards it's end.

Back in level 3 , just beyond and below the climb up to level 4, a short crawl leads off left, into the top of the rift leading down to Multi Level 2. After sliding through the rocks, traverse over the rift until a slippery chimney climb down to level 2 can be made. [Here the various short routes through the chamber's boulders, as yet have nothing to recommend them]. Back along the level 2 rift is another junction, the right leads back (over the very narrow Multi Level 1 containing a small stream), to the choke at the end of the Tall Rift, (which was the original, but now blocked up entrance to the Multi Level Series), to the left a wider section soon chokes.

Back in level 3, at it's far S end, there is a 3.5m climb down into a cross junction. Straight on goes up through a dug out choke, diminishing upwards into fissures. To the left, what was a very narrow rift containing most of the draught and the sound of a small stream below. Presently this terminates in a dangerously loose dripping choke, hidden off on it's right hand side is a 2.4m diameter chamber with an alarming hanging boulder ceiling.


Having taken the left side step, 2m down off the penultimate Autumn Frenzy ladder, the 15m phreatic passage is followed, to pop up through the March 2003 "Testo" Breakthrough Point, into the spacious Breakthrough Chamber. Another four passages radiate from here but the largest heading N, leads on to a stack of boulders which is climbed up through via the gap on the left. Dome Chamber diffuses out in front and down to the right.

To the right leads to the short Dog Tooth Chamber Short Round Trip and Dog Passage. [At the base of the rubble slope the passage off on the right forms a loop back to the Breakthrough Chamber, by following a smaller right turn where it widens]. To do the Dog Tooth Chamber Short Round Trip climb 2m down through the gap in the boulders at the end of the right wing of Dome Chamber, the round trip rejoins this point from the rift passage on the left feeding over these boulders. Continue down the passage to a staggered cross junction, slightly left and straight on is the short Comfy Crawl, at it's end climb up 3m to another confused junction. Bearing left follow the most obvious continuation to a large T-junction. [Opposite the undercut wall sports a mostly crawling route linking up to the Dog Tooth Chamber. Right the lower route leads over a pool to a dripping choke, and the upper route to further dripping chokes]. Scramble under the boulder on the left and continue over the breakdown to enter the top of Dog Tooth Chamber. The best crystals that lend their name to the chamber, may be viewed in the walls of the gallery on the right. The round trip is closed by crossing the chamber and stepping up left to follow the continuing rift passage.

Dog Passage may be explored by entering the lower section of Dog Tooth Chamber, usually by scrambling down the rocks under the roof below the crystals. This leads to a bedding area, the 3m climb down into the Dog Passage is found at the left end of a step up to a reduced bedding area. The passage leads on past the Dog Corner Dig, [which when open provides a link to the end of the La La Slide]. After passing the dig an area of breakdown is negotiated, some of which may be avoided taking a low crawl along an undercut of the left. Various points on the right loop up to differing sections of the passage coming back over itself. Staying left eventually pops up into large passage, of which the end choke has been sound tested to come up in Nurden Hall. [Also towards the end in the floor on the left is a hole leading to a squeeze, pushing on comes to a traverse along a rift, another very tight squeeze at the far end rebirths into the base of Dog Tooth Chamber]. Following the passage back over itself [off on the left an awkward and unrigged pitch can be found that drops down 6m to loop into the Original Canyon Passage], leads to a high roofed junction. Continuing right leads to the Tubby Dungeon connection low on the left, but stepping up into some fine phreatic passage leads to the aptly named La La Slide.

Continuing N straight on across Dome Chamber, passes through a similar feature, then down a ramp of rock (originally a precariously balanced choke). [In the low area on the left a dug connection through to the Mallie Rifts can be found, providing a slightly more sporting alternative, to the normal Nurden Hall route]. Continue up another longer rock ramp to enter the spacious Nurden Hall, [the main passage continues rising N for a further 50m, to the level of the entrance chamber, where it chokes up leaving only a few minor oddments to push along]. The main route on is under the E wall on the left, soon emerging into another sizeable chamber, which is crossed on it's right.

[Following the left side of the chamber by means of a small ledge on a large left slopping boulder leads to a crater. Moving down the crater and continuing through the rocks, bearing back left leads to the Mallie Rifts or continuing on right leads to the Taylor Rifts. At some cemented rocks a 2m move down drops on to the head of a choked rift, descend the choke to follow the rift floor. Just over some boulders the passage branches.

To the right a traverse, (passes another left passage that loops via a squeeze to base of the passage beyond the Linking Passage), leads to the initially impressive Original Canyon Passage. Opposite where the traverse enters is The Breach, a large but short section of water sculpted passage, that terminated in a 8m high choke. Digging up through the head of the choke, and in the chamber above have resulted in tens of tons of rock forming a ramp up to an active dig in the structurally threatening chamber above, plus a further 25m of NNE passage. To the left the Canyon Passage soon chokes, but to the right it's tall smooth straight sides disappear SE into the distance, gradually encroaching together, and eventually pinching leaving various tight rifts to struggle along].

To the left the passage can be traversed until a right turn into the Linking Passage is encountered, or followed at floor level to climb up at the 3 jammed rocks to gain the Linking Passage. Left at the T-junction continues for 50m before pinching out, right soon leads to a choke and the base of a 10m pitch that provided the original access into the Canyon Series.]

Continuing right through the chamber leads a short flat out crawl, to another smaller chamber. [The rock pile tumbling down on the right leads up to the Karver Galleries, and the hole in the floor leads through to the upper sections of the Taylor Rifts (and the original 6m access pitch)]. At the left end of the chamber at the base of a choke, a short dug out connection crawl, leads to another short section of shattered passage. Another dug through connection leads to slightly larger fractured section that soon emerges into the expansive Canyon Halls.


[Up on the left a rock slope rises SW to a wide collapse chamber, back on the right the passage continues to levitate 15m above the Original Canyon Passage, and another smaller passage diverges off on the right to the Mini Iron Mine].

Moving NW into the next main hall, one of several openings on the left, lead to the beautifully sculpted caver friendly Phreatic Causeway, worthy of a visit if only for the first 60m, until the point the roof dips down. [On the corner around where the passage ceiling switches from flat smooth with rounded cornicing, to the darker iron stained rugged chert, is a junction chamber on the right. In the floor of the chamber is the Phreatic Drop (a reasonable alternative to The Shattered drop especially going down), leading down to the floor of a rift passage that is followed back NE to come out of the 2nd left in the Six Way Junction. Also from the chamber is a route that connects to the complex upper series, connected to the 2nd right of the Six Way Junction].

Back in the Canyon Hall, opposite the Phreatic Causeway entrance is a gap in the floor leading to The shattered Drop. BEWARE this area is very fractured so stay alert and take care. Easily traverse across to the first ledge of the heavily gardened choke, do not venture across the take tape warnings above this ledge (prior to gardening the choke was avoided by a 7m ladder pitch). Climb easily down the choke treating the rocks midway with caution, particularly avoid pulling on them when climbing back up, using the opposing solid walls as much as possible is safest.

Canyon Continued is followed NE usually by traversing straight ahead, or by taking the twin passage up on the left, until Six Way Junction. [1st left is the incoming twin, 2nd left goes to the 3rd ladder bypass and the continuing traverse bypass, 1st right leads to various oddments, 2nd right leads via an upper eye hole to a complex upper series]. The main way on is to continue traversing NE, however a traverse bypass is possible by taking the junction 2nd left, then taking the next two right turns, to turn left into the main passage, which is followed along it's initially muddy floor until a climb up rejoins the main level. After the traverses the rift turns right under some interestingly suspended rock slabs. A few more turns and a passage entering on the right, [ which loops back to the Fin Pillar Passages], Fin Pillar Junction is reached.

[Climbing up 8m, paying careful attention to the potential soundness of the holds, accesses yet another complex upper series. Right traverses past the Fin Pillar, and continues to a deep widening, at the base of which sprouts two narrow rifts. The first heading SW, loops back to the main Canyon Continued, while the second heads SE straight and narrow, eventually stopping at a run-in mud choke, inletting a tiny stream that runs down a soon impassable narrow passage on the right. Over the widening a short continuation soon splits up to various terminations].

Canyon Continued continues left as a tall rift (initially WNW), move 4m down to the floor level where swift crab style progress can be made. At the 1st branch go left, [right leads to another sizeable rift passage soon ending in a choke], at the 2nd branch go left again. [Right leads to the extensive 2004 East Series/New year Series. Sporting two possible loops back to the main Canyon Continued, and a strenuous upper series containing various calcite formations. These usually occur at the points where passages pass from underneath the surface capping of sandstone, that covers all of the cave south of these points. There is also a taxing connection with this upper series to the final Plummet Junction upper series]. When forced to climb up 3m over rocks a passage enters on the right from a shattered widening, [this loops to the 2004 East Series]. Continue until forced to climb 4m over choked rocks, where another passage enters from the right, [this also loops to the 2004 East Series]. At the shatter corner bear right N, (through the rocks on the left is a series of narrow rifts), after a muddy pool this dog legs and becomes adorned with flow stone, marking where the cave emerges from under the surface capping of sandstone.

The rift materialises into the long, wide and deep Plummet Junction, (primarily acquiring it's name from a 4m fall while climbing at it's NE end, that fortunately only sustained an injured pride). [The passage to the left has been pushed for 25m, but awaits some intrepid anorexic to take up the gauntlet]. Bearing right the gash in the floor is traversed over (some prefer to climb down and scramble out the other side), to reach the junctions cross roads. [Right leads to a choke, passing over a deep hole, where running water may be heard in very wet conditions, however the base pinches out, and trust me the hole is narrower than it looks! Ahead the main passage also chokes, but an 8m climb up gives access back over the head of the main passage. A very tight, exposed and committing traverse gains access to another upper series, now somewhat contortedly linked to the 2004 East upper series, negating the need for the 'sensicle caver' to cross the traverse.]

The stooping then crawling passage on the left, soon meets a T-junction. [Straight on is smaller set of crawls, bearing left comes out under the Muddy False Floor, onwards leads to a choked area, containing a semi choked rift rising upwards, that when dug is presently the main hope left for further progress at this end of the cave.] Taking the left option leads via some meanders to the Deep Rift passage, which is the recommended terminus for most visiting groups, as pushing on further involves becoming extremely damp and muddy.

[The Deep Rift has been inspected, but becomes very narrow, even where water coming off the muddy false floor in wet conditions sinks at the lowest point, there is presently thought to be little hope of progress. Traversing to the left also pinches up, but a wide upper off shoot is known to communicate with the upper series. Traversing right leads onto the Muddy False Floor, which is squirmed along passing through a well lubricated squeeze. A small window on the right accesses a roomy but soon mud choked section of passage. Ahead the squirming continues through flow stone to brief relief at a left turn. Above a small window, is forced up through, to an 8m high flow stone lined aven, and a large section passage choked within a few meters by huge boulders. Bolt, then free climbing of the aven revealed no open ways on. There are also no plans to tackle the choke; any digging activities here would have to take great care not to block the exit window that the whole area funnels towards].

The 30m entrance shaft and 12m scaffolded shaft to access the main cave, have permanent fixed steel ladders, however life lines for these are not provided.

The entrance lid should be closed, while groups are underground.

Access : Contact Jan Karvik.

Access : The entrance to the cave lies on Forestry Commission Land and as such comes under the Access Agreement between Forest Enterprise and FoDCCAG.

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