Hang Nguom Nuoc 1
As with all good tardises, we would never have imagined the amount of cave this limestone outcrop would yield when we first arrived at what Paul termed “that tiny limestone noggin”, and what the Minister for Culture and Education had assured us was the best caving area in Yen Thuy District. The setting was rather idyllic – a diminutive, isolated limestone outcrop, edged with semi-circular bays and situated away from road and village. The immediately adjacent army firing range seemed but a minor blip, all else considered. One of the bays fringed a single bedroom house on stilts with several adjacent modest vegetable plots and a few scattered chickens scratching for grains and insects.
A shallow streamlet, perhaps a yard or two across, issued from a small opening in the rock nearby, flowing in a lazy curve around the crops and off to the north. Above, in the hillside behind the stream, we could see a black, circular hole. Further along the edgeof the outcrop, and partly obscured by vegetation, the presence of swamp grass by a solitary blue puddle indicated a stagnant resurgence.
Three entrances to examine! The minister’s face beamed with an unspoken “I told you it was superb”. Never mind that these specimens were lilliputian compared with what we had come to expect from Vietnamese cave entrances - we did not have the heart to disappoint the eager minister. Contriving to look suitably impressed, we split into a dry and a wet entrance team and set off.
The wet team consisted of Martin Holroyd, Gareth ‘Sweeny’ Sewell, Anthony ‘Woody’ Wood, and myself. Although the entrance had looked minuscule from the homestead, once standing in the stream we could walk in without having to bend over. Inside, the passage enlarged substantially and we waded along in comfortable space, grudgingly admitting that this was not that bad at all.
The going was very easy, if mildly irritating due to occasional vicious boulders, lurking under water to attack the shins of the unsuspecting caver. After about 600m we reached a second entrance. Intriguingly, this entrance had witnessed substantial man-made modification. A concrete and stone pier allowed for easy landing of cargo. A naked wire running along the cave roof ended in a solitary light bulb that dangled precariously above the man-made pier. Hidden behind a natural rock pillar, a sizeable still explained the nature of the nocturnal activities the modifications were designed to facilitate. The entrance opened up into an enclosed doline with parallel high level entrances to the right and left of the distillery entrance. Inside, a nearly water filled passage with a semi-circular diameter led into the black distance. Woody decided to have a quick look along this passage and disappeared. The rest of the team continued surveying along the main stream, leaving exploration of the side passage and doline for the return journey. Little did we know?
The continuation of the stream distillery entrance is reasonably decorative and might, at a pinch, perhaps qualify for a show cave of local importance. Two shallow-bottomed, single occupant boats moored on a ‘beach’ by the side of the stream testified to the navigability of this section of the cave. Not much further into the cave, we encountered high level development situated directly above the stream. As we surveyed along this towards the entrance, we half expected to meet up with the dry team, but this apparently obvious connection was never made. Back in the stream, several stretches boasted sizeable white stalactites and flowstone, and at one point the stream widened into a chamber containing straight columns, like pillars holding up a vaulted ceiling. The water was warm compared to the outside and the air thick with steam. With the pillars, this gave the slightly surreal impression of surveying through a Turkish bath.
Hours later we had run out of wading-depth stream, had first crawled (Martin H : “ if this does not improve I’ll turn round”) and then walked along a wide, muddy, flat-bottomed passage interspersed with puddles. Finally we reached a dry, spacious chamber, home to bats and arthropod wild life. Two ways on were found. Well, the minister had announced the cave was ‘very complex’.
We first went for the slot in the floor, named ‘Thumbs Up’ by Sweeny. Thumbs up turned out to be a small (2m x1.5m) phreatic passage of constant dimensions, trending (south in a nearly straight line, very much like a drainage canal. To add badly needed interest, vicious, jagged submerged boulders, occasional swims, and various arthropods made a re-appearance. A side passage quickly ended in a sump. Shortly after, we encountered an eerie, thick, tangle of long, tentacular white and brown roots, hanging from the walls and surface and wafting around in the stream. These and fresh tasting air strongly indicated that the surface was near. Nevertheless, the passage showed no signs of wanting to end. With time running out we decided to turn round.
After a day’s caving in this ‘tiny limestone noggin’, the main passage remained unfinished, and a further two side passages, two holes in the doline, and the stagnant resurgence next to the original entrance were waiting to be explored.
Martin Holroyd had had enough of the unsatisfactory dimensions of this cave and went off to do something else, but Sweeny, Martin Colledge, John Atkinson and I returned to finish the caves in the ‘noggin’ the next day.
The canal ended in a duck after another 200m. Martin C explored the continuation, but due to the low and flood-prone nature of the passage, this part of the cave was declared finished. Returning to the dry chamber, the second way on (have we got no names for these features???) led through a series of flat-out muddy crawls and wallows into a final chamber with a steeply angled, solid, bedding plane roof. This draughted, and tiny chinks of daylight suggested another entrance behind a solid, impassable choke.
The flooded side passage near the distillery went for over 800m to a sump. Most of the passage could be accessed by easy wading on gravel and sand (no lurking boulders), although we had to swim on occasion. On the way back, I discovered a side passage we had missed on the way in, and had hence omitted to create a survey station nearby. This was rather embarrassing, and we spent some time reconstructing a number of non-permanent stations from drawings, memory, and repeat measurements, until we were confident that we could tie this passage in. Beautiful white limestone and a solid mud floor soon led to a third entrance, opening into a semi-circular bay. This one was similar to our original entrance, but minus a farm house. GPS readings indicated our original entrance was a mere 500m away in a straight line. A combination of following the edge of the noggin and climbing over a pass saw us back at our first entrance. Two days into the tiny noggin, and we still had the holes in the doline and the stagnant resurgence to survey.