Ogof Igam-Ogam - Description



The entrance to Ogof Igam-Ogam is in the west bank of the Afon-Nedd gorge which carries the river southwards towards Pont-Nedd-Fechan and the Neath River itself. The east bank contains the Little Neath River Cave, a significant cave containing large stream passages and many beautiful formations, whilst the west bank is devoid of any large cave passage, holding just a few small sites. This blank area of limestone has long been of interest to local cavers for it contains a considerable number of resurgences that take their water from the Pant Mawr area. The actual Igam-Ogam entrance is a small phreatic tube facing downstream, so well hidden that an unobservant explorer could easily pass it by when exploring the river downstream.

The entrance tube is big enough to permit crawling until after a couple of metres the tube terminates at a dry calcited inlet that follows NNW, up-dip. At this corner another crawl, this time even smaller, follows a small rift and zig-zags into the hill over several gour pools to a flat out squeeze over a gour rim and into a low bedding plane (containing many gours), crossing the dip and going into the bank due West. This flat out bedding emerges into a comparatively larger section of cave which runs for over 15m NNW. Although running up-dip this passage actually descends by almost a metre along this length. Several knee-deep pools are waded through and a small ox-bow containing several more gours is passed and the passage degenerates again into a flat out crawl over gours for another few metres. An attractive mini-cascade drops the explorer down into a waist-deep pool and then another crawl, this time pebble floored, is negotiated down a ramp and under a low, awkward duck to the start of Swap 1.

The entire complex of three swaps and the passage in between is known as the "Waters of Lathe". These extend for a total distance of 61m and descend southwards, down dip, dropping in altitude 5m from the start of Swap 1 to the end of Swap 3. (The "Water of Lathe" were a mythological river in Hades which produced forgetfulness of the past, hence, after immersing oneself in them, on surfacing one found one's true identity.) The swaps are all perched above Suzuki Chamber and can therefore be pumped dry given the correct apparatus. (During the initial exploration of the cave by Croydon C C, a submersible pump and a Suzuki portable generator were used to drain all swaps almost dry. At the moment a diver is necessary for this draining to be successful but if pipes were correctly laid insitu this would not be necessary.)

Sump 1 is the longest of the three at 22m and is probably the most technically awkward to dive. A low submerged tube only 2ft high continues almost straight for l0m but for a slight left-hand (going in) shift. Under usual conditions, when the swap is full, two small airbells are found after a slight lowering of the roof, the first being long and high enough to permit use, the second low and less breathable. Under this second airbell is a man-size 2½m pothole containing an opening less than a metre high at its base. This squeeze under an arch is difficult when the sump has been drained and reportedly distressingly awkward when dived. A pebble slope leads through another left ward shift in the passage (this time narrower than before) before leading up and out of Sump 1 and into a narrow rift passage of almost comfortable proportions.

After almost 13m of clean rift passage has been traversed the roof descends to within a metre of the floor and Sump 2 starts. Swap 2 is an easier dive than Sump 1. It is a 21m long tubular passage containing a nasty projection half way along its length. It is only lm deep and follows an almost straight line to a S-bend corner, swinging first right then left, with an small airbell just before another pebble ramp up terminates the swap.

11m of very nicely carved, clean washed, passage containing a few straws leads to the final swap in this series. Swap 3 is roomy, straight, only 3m long and lm deep and could therefore be considered to be the only safely free-diveable swap in Igam-Ogam if the need ever arose. Similar to the last two swaps, this also ends in a rising pebble floor.

After 4m of attractive carved passage, similar to before, the entire nature of the cave and geomorphology of the rock suddenly changes when the rift starts to drop quite steeply. The rift passage zig-zags left and right erratically and descends over 9m in depth in as many metres of horizontal passage. The caver is finally left suspended over a large drop as the previous rift passage from the swaps intercepts the roof of Suzuki Chamber and drops right into it. A bold step out onto a convenient boulder pile enables the explorer to clamber down into the centre of Suzuki Chamber.

Suzuki Chamber is approximately 8m square and is aligned along a major fault line, (as is much of the lower section of the cave) that runs in a NNW/SSE direction. The ceiling of the chamber is about l0m up and an aven centrally located on the fault line adds another 5m to the height. The chamber is floored by many very large boulders made from a black limstone D2) reminiscent of that which is found in the Marble Showers area in OFD II. Very similar rock also comprises the last sections of the roof passage before it enters the chamber. At the end of the chamber, along the fault line in both directions, there is evidence of a false floor having once being present. This is particularly so against the east and south wall of the chamber. The north wall of the chamber leads down a broken slope of large limestone boulders with much calcite veining in evidence. This heads towards the terminal sump (see later). The aven has been climbed to point where no more progress could be made and another roof tube similar to the first was located. Numerous snail shells were found here but the passage ended after a few metres.

The Snorer's Annex may be reached by a careful 3m climb between boulders on the eastern side of the main chamber. A spacious bedding plane over 3m wide and lm high may be followed over a mud floor holding a meandering small stream to a blank rock face, where the trickle sinks. Although the left hand wall is solid the right is comprised of boulders and may be penetrated to gain access to ante-chambers of various sizes, one over 5m x 8m containing straws. Large quantities of water and small flood debris have been seen emerging from this boulder pile and it seems that this part of the cave may be connected to a sink in the Afon Nedd Fechan 18m above the level of the passage. Many of the boulders in this area have yet to stabilise and care should be taken.

Clambering down the boulder slope in Suzuki Chamber a hole just to the left of a large black slab leads via a low, gritty crawl to the deepest currently known passages of Ogof Igam-Ogam. The crawl steadily becomes a stoop which in turn increases in height to a walking passage. This square shaped passage meanders its way north for almost 30in. Most of the walls are mud coated and it is suspected that much of the passage beyond that leads to the terminal swap floods completely. More of the black limestone is seen in this passage and although the passage is theoretically going up-dip, and so therefore going up hill, the actual altitude of the cave seems to drop, as many small rivulets and trickles bear witness. A short section of streamway descends into a large forked junction where a number of stalactites and boulders are found.

Going left at the junction a motly collection of stalactites are gathered around the entrance of a muddy stooping passage heading back towards the main chamber, these ugly looking formations are known as the "Flying Pickets". A 2m square passage heads almost due SSE for 35m passing a calcited pile of boulders on the left with an inlet flowing down over it. The passage apparently terminates in a large boulder pile blocking the passage. A way may be forced through at the bottom of the choke and access is gained to a continuation of the passage above the obstruction. The continuing passage's dimensions are more impressive than before being 3m wide and nearly 2m high. This unfortunately only lasts for 23in at which point the muddy floor rises to meet the ceiling and the cave swings abruptly north and then west. After a further 8m the passage ends at a blind wall. As in the Snorer's Annex one wall is solid, whereas the other is made from a densely packed boulder pile hosting an inlet. Several minor passages in this area have been located but none can be followed very far.

The largest continuous section of passage in the cave is "So Long and Thanks for All the Fish" which is over 190m long and heads directly along the fault line NNW until it sinks into the terminal Sump 4. This starts from the junction where the Flying Pickets are located and leads straight on from the passage which leads off from Suzuki Chamber (see above). The dimensions of the passage start respectably at 4m x 2m high but soon degenerate into an almost flat out crawl in a very wide, wet, bedding plane. Mud banks are abundant towards the final swap and much evidence of complete flooding is seen decorating the walls and roof. After the passage gasses through a 21m long wet canal that could almost be considered a duck, the cave resumes larger proportions. The passage now resembles a typical stream rift passage, intercepting two small chambers about bin long and 2m wide containing much flowstone, columns and stalactites and numerous short straws (particularly on the left hand wall). Flood debris does not seem to permeate to the higher sections of these chambers, the ceilings being over 21i1 high before getting progressively too tight to be foil owed as one nears the roof of the rift. Splashing through several shallow pools a corner is reached. After traversing more pleasant small stream passage an S-bend staggers to the right, next to a large stal. boss 1½m high. The fourth swap starts here in a large knee-deep pool. It follows the passage north and has been dived for a distance of about 9m where the way on could not be found. The start of the sump is very low and possibly slightly loose. Several roof tubes in this area have been looked at but none can be followed far.

Ogof Igam Ogam - The Name

The earliest references in the log-book are to Paniwnyk's Cave after the discoverer. Later it is referred to as Ogof Gwib which had been coined using an English/Welsh dictionary. It was reckoned to mean "wandering" and referred to the meandering nature of the entrance series. However by the end of May / beginning of June the name Ogof Igam-Ogam which had been suggested by Clive Jones (SWCC), begins to appear as the standard name. It means Zig-Zag Cave.


Paul Stacey