Naga Caves – Nong Khai and Loei – June 2009


I have been working on writing a guide to the caves in Loei in north-east Thailand. Most of the caves can be visited on day trips from home, but I had reached the point where the distances involved weren't sensible. The next option was to spend a couple of days there. Terry had a spare weekend so it was arranged that we would collect him and Noi from the bridge in Nong Khai as they came across from Laos. This plan worked and we were on the road by half nine on a Friday morning.

We set off following the Mae Khong river upstream, stopping in Si Chiang Mai to look across at Vientiane, the Lao capital, before continuing our journey. It wasn't long before the first 'wat tham' sign post was seen and we were detouring off the sealed road and into the fields. For anyone caving in Thailand I recommend learning to recognise the Thai words for cave – ถ้ำ (tham)  - and for temple cave – วัดถ้ำ (wat tham) – as this is the key to finding many of the caves as any signs are usually only in Thai.
This forest temple, Wat Tham Pu La, wasn't waymarked in the GPS so was a new site. Arriving in the temple grounds we found a large wooden temple still under construction, but as the surrounding rocks were sandstone didn't bother getting out of the car to have a look. Back where the track left the main road a sign to Tham Bo Pha Se was seen. However, we again didn't bother going to look for it as the visible rocks were still sandstone.
A few kilometres further along the road a sign, in English and Thai, was noted to Wat Tham Si Mongkhon. After 20km following the unusally frequent and helpful signs we arrived at the wat. Again the surrounding hills were all sandstone, but for some reason we decided to get out of the car this time and look around. This is a large temple and by following a path down hill we came to a shrine and a cave entrance! A couple of steps led down into what looked like a small, scrotty hole and a sign above said it was called Tham Din Pieng. Close by a stream sank into the sandstone and a couple of holes also seemed to go down into cave passage – this was looking promising. An old gentlemen was waiting at the shrine to act as a guide so after paying our respect at the shrine (for good luck as caves are dangerous places) we were instructed to take off our sandals and flip-flops and along with a Thai lad who had just turned up set off into the cave.
I wasn't expecting much. The small entrance led to the stream that was followed for a couple of metres to a short section of deeper water in a triangular shaped passage where the larger farang caver had to squeeze along, but got through without getting wet above the knees. This opened out into a larger passage / chamber about 1.8m high. We heard voices behind us so waiting for another group to catch up before continue the exploration. This cave was turning out to be a real surprise.  One bed of sandstone, about 1.5 to 1.8m high, must be very calcareous as every joint had been eroded away to form a maze cave with a four-way junction every 3 or 4 metres with slightly larger chambers in places. Although the cave has been electrically lit take care as I got a slight shock when my back brushed one of the fluorescent light fittings. 
We continued to follow the guide as he took us a few more metres down stream. At the point where we turned round the stream passage was seen to continue about 70cm wide and a metre high. The cave is said to continue all the way to the Mae Khong which is about 20km to the north. This is, to put it gently, highly unlikely, but the water must come out somewhere. Trying not to loose the guide we turned around and followed what seemed to be a different stream back up hill. The Thai who had joined us was a local and mentioned coming here years ago before the electric lights, using candles and having great fun trying to find the way out again. At one point there was a squeeze under a stalactite (which must be unusual for a sandstone cave) which the natives passed with ease, but the fat foreigner got quite soggy. Eventually we reached the bottom of a pothole where 5m of fixed metal ladders took us back to the surface about 50m in a straight line to where we had gone in.
Terry and I were very impressed. Our guess was that we had seen 200m of passage and it was by far the longest sandstone cave we had been in. A return visit is required with proper kit (i.e. footware, lights, kneepads) and it is advisable to survey on the way in as you may need the notes to find the way out. 
This cave got us thinking. What if this bed of calcarous sandstone is found throughout Isaan? There could be hundreds of 'proper' caves out there waiting to be explored. Many years ago Claude Mouret had had an expedtion to north-east Thailand and reported on sandstone caves up to 700m long and others with water or streams, but no one else seems to have done any cave exploring in the region as there is very little limestone. 
Walking back to the car I started wondering if this was the 'Naga Cave' reported as being over a mile long by a cryptozoologist. Getting back home I had another look at the website with his report, In The Coils Of The Naga. The photo of the entrance was the same entrance we had descended. The report is more than a little over the top and we didn't come across the monster snake.
The next cave we had a brief look at was Tham Pha Baen near Chiang Khan in Loei. I had been here 18 months before and the monk had reported it to be a long cave that went all the way to the Mae Khong, this time a slightly more believable 3km away, but it was at that that time of year too wet to enter. This time we had a good scout around. We didn't find any more passages than I had visited previously. What we did find was an interesting snake. This was like a 'reverse' Cave Racer in that the black with yellow stripes was on the front part of the body while the tail end was plainer without much patterning (in normal Cave Racers it is the other way round). The black eye stripe wasn't very distinct, but did continue around the back of the head. Despite the odd colour scheme the snake behaved like a normal Cave Racer and disappeared into a crack in the wall before it could be photographed.
One cave I have wanting to visit for a long time was Tham Mahotan which is about 50km south of Loei town. Twice I have turned up to find the gate closed and didn't get into the temple grounds. This time I got Yuphin to dial the phone number painted on the gate to speak to someone about access. Much to our surprise the gate opened after she dialed the number – it was an automatic gate opened via telephone! It wasn't long before we were in Tham Mahotan. This 230m long cave is a large phreatic half-tube that eventually chokes. It is electrically lit and sees a lot of visitors resulting in a lot of damage to the floor and graffitti.
It was time to start heading back to Nong Khai. After stopping at Tham Pha Sawan to look at the serow (a type of mountain goat) that they have in a compound there we continued on to Tham Erawan. On the way we had a quick look at Tham Wang Thong which was conveniently beside the road. As Terry and I reached the plaza outside the cave I noticed a monkey. This wasn't one of your usual scrawny temple long-tailed macaques, but was the size of a Toy Poodle on steroids. What's more he wasn't very welcoming giving us a fine territorial challenge of flashing eyelids before marching up to us and baring his bright red arse in our direction. I was armed with only a Q40 which wasn't going to be much use, but was more than Terry had so he wisely stood behind me. Fortunately the monk showed up to assure us that the monkey only bit children and he only wanted to play. We sneaked past and got a quick look at the cave, a 30m diameter, day lit chamber with many Buddha statues, before the monkey joined us in the cave resulting in us returning hastily to the car.
Tham Erawan is a very well known pilgrimage site and is signed from as far away as Udon Thani in the east and Loei in the west. I had been here before and didn't fancy ascending the 650 steps. However, I did recommend it to Terry and Noi who dutifully headed off up the hill. An hour later they returned having enjoyed the large 400m long passage with fine views over the surrounding countryside.
That was the end of a successful weekend of caving with various previously unvisited Loei caves having been found. Of much more interest was discovering that proper caves can be found in Isaan, a huge area of north-east Thailand that is just about untouched speleologically.