Nguom Sap was originally found during the 1997 expedition on the last day of the trip. It had been explored for 2km with many leads left unexplored. In fact, no passage had been explored to a conclusion so our hopes were high for this cave. The cave is in the Ha Lang district and on the maps the river was seen to be headed into China a significant distance away. The access to this cave is very easy and it is possible to drive within 10 minutes of the entrance. A short walk across paddy fields leads to the entrance where a sizeable stream enters the cave. On our last visit in 1997 a much larger stream was present but this year much of Vietnam like many parts of Asia was experiencing a drought.
The team split up into 3 groups all armed with survey gear and a copy of the survey to check out leads from the previous trip. The aim was to explore, survey and photograph as much as possible in the time available. Nguom Sap is an excellent cave with many levels of development; hence the potential was quite good for a significant system to be found.Following the stream from the entrance, a lake is reached (Hippo Crossing) and wading to the right soon leads to dry passage. The water sinks somewhere in the lake and the only other place it is seen again is to follow a passage back over the lake, which has a good draught for 200m to a short drop with the sound of water below. This was the limit of 1997 exploration and one team came armed with equipment to drop this hole. Pete ‘Grabber’ O Neill hurriedly attached a ladder and descended to the water. The sound of running water was very inviting, however the passage quickly sumped and one of our most hopeful leads was finished.
Over the top of the pitch a passage continued so the rest of the team left Pete to detackle whilst they surveyed a passage which was getting larger all the time. After a couple of hundred metres the passage led into a huge chamber “Champagne Supernova” with what looked a number of passages radiating out. One passage in particular is spectacularly decorated and the huge curtains that cover the right hand wall are a tremendous sight. This gour filled passage was again grabbed by the notorious team member who had no sooner got himself to the front before it quickly choked.
While the rest of the team was painstakingly surveying this large chamber an obvious passage was seen at the top of the boulder slope and Grabber decided he had better try that. The survey team made their way towards the passage only to be greeted by a dejected Pete with the words ‘choked’ again ringing around the chamber. At this point it was decided to give Pete the instruments due to the fact he was becoming a Jonah and this should stop him sneakily grabbing any future passage.
Back at Hippo Crossing the flood overflow passage is followed downstream “Waltzing Along” passing a number of side passages which were checked out and quickly finished. About 1km into the cave the passage turns to the left and a high level can be entered on the right. In 1997 the lower passage was surveyed to the start of a swim. However because of the drought in Vietnam the swim no longer existed and the team clad in wet suits were able to walk through this open passage. The walking passage continued to a large breakdown chamber ”Destiny Calling”. Bending to the right the passage continued, reaching another area of breakdown. After this some pools were reached which could be waded through. The passage became smaller with a lot of decorations. The way on was up through the formations and then a drop to the stream led to a swim and finally a sump after 870m.
Continuing along the high level passage, ”Wembley Calling” is reached, an area the size of a football pitch and amazingly flat. From here a number of leads were present and all were checked out. Two small side passages had previously ended at low muddy pools. The left-hand passage connected back to a small passage the other side of “ Wembley Calling”. The right hand passage connected to the main passage before the junction. Both pools had dried up, although the passages were both very muddy.
Two leads around the well-decorated chamber were surveyed. One ended quickly in a pitch to a choke. The other led to 250m of well decorated high level passage ending in a calcite choke.
The end point of 1997 “Wonderwall” however proved very interesting. The right hand passage led to a short drop of 5 metres to a muddy continuation. We quickly slid down this thinking it may be interesting on the return but with no tackle we had little choice. We continued surveying in a passage of 10m by 4m which divided and the right hand branch soon led to a boulder choke with a strong draught coming out but no way through.The main passage “Acquiesce” continued again to a boulder choke, which despite the draught no way on was found. However we had surveyed 405m.
The climb proved a little tricky on the return. The mud and steepness of the slope was proving a real obstacle. By making a pyramid of people one member was able to claw his way to the top. Then using the survey tape, which was surprisingly strong, all the other members were able to just climb up back into the main passage “Wonderwall”. On this team was a Vietnamese member from the University who was on her first trip underground. I do not think she was too impressed with our improvisation and was very pleased to reach the top of the climb.
Back in the main passage the now overheated team explored the left-hand branch. Following the very large passage up and over a boulder slope led back down to a large passage“Headshrinker” containing a small stream. The decorations in this area of the cave are quite spectacular and many huge columns and gours are seen. This passage was followed for 440m to a draughting climb. This was climbed to the surface to emerge in an enclosed doline with a river in the bottom, which could be seen leading to a large cliff face. This was left for another day whilst other leads were checked out in Nguom Sap.
Before we exited the cave we managed to photograph some of the pretty parts of the cave. The team all left the cave just before dark, in time to get back to our transport after a very successful trip.
Nguom Sap was surveyed for a total of 5270m with a vertical development of 82m. This is the longest cave in Cao Bang province and because of the continuing leads across the next doline we hoped it would prove just a small part of a larger system.Due to the many levels of development a lot of cave was explored in quite a small section of the limestone massif.
This spectacular cave was a great start to our caving in Cao Bang province and gave us much hope of future discoveries in this beautiful area of Vietnam .