Khao Sok Diving
Khao Sok Adventure
I live and work on Koh Tao and along with a few buddies and my dad, who was over for a visit, we decided to get off the rock and take a few days to explore Khao Sok National Park. Given that the parks main feature is 165km sq lake we thought we’d throw some diving equipment in the truck just in case we felt like a dive – who were we kidding? We had heard there were many stunning rock features that due to the damning of the Pasaeng River were now underwater.
We travelled by night boat to the mainland and drove straight to Khao Sok, arriving lake side by 9am. The view from the pier was fantastic already and was just a taster of the scenery to come. I’d been told of massive limestone pinnacles erupting out of the emerald green water surrounded by some of the oldest rain forest surrounding it making for lush vistas.
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To Dive Or Not To Dive
The longtail transfer to our accommodation was to take just over an hour and the scenery was nothing short of breathtaking. On the way our longtail driver, who had spied our dive equipment, told us about Pha Deng (Red Cave), a structure that we had heard about from fellow divers before. We had not intended to dive straight away but with so much water, the temptation seemed too great. It was swelteringly hot and our driver told us the site was actually on the way. My dad has his fishing gear with him and was eager to cast a line – so the decision was made.
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Orientation
It should be noted at this point that we are very experienced recreational and technical divers and instructors but, even still, we thought it prudent to just pop in and have a quick dive to check the conditions and environment first. We’d only ever dived in fresh water a few times and certainly not regularly and clearly we had not dived here before. We had talked to other divers before we left and had as much information as we could before going and our guide was a font of information too.

Pha Deng
The first few metres were bath-water warm and a little milky but beyond that the water chilled to 27c and became crystal clear. We had planned a short 20 min orientation dive and inside only a few minutes it was clear that we would certainly be diving again before checking into our accommodation. The stalactites flowed down the side of the pinnacle like melted candle wax forming huge structures that dwarfed us, some were over 10m long. These formed an overhang like a ripped curtain which we swam around in awe marvelling at their size and intricate design. Our torches illuminated a huge space behind the limestone curtain, full with more amazing structures and curious cat fish, which we chose to explore on the next dive. We were excited to get to the surface to talk about what we had seen and eager to discuss our next dive.

Behind the stone curtain.
On the next dive we planned to explore the huge grotto underneath the stalactites. We planned for a 45min bottom time to explore. Swimming passed the huge tree was a belittling and surreal experience and once passed the curtain, the grotto opened up amazingly, displaying a chaotic array of architecture. Stalagmites and stalactites formed columns in places and huge altar like plinths rounded with time.
Fresh Water Feline.
Crazy curious cat fish make their home in Pha Deng and continuously added a comedy element to the dive. Clearly they were not sure what to make of these huge noisy bubble fish with bright lights. On numerous occasions we came nose to nose with them and they frequently caused me to jump or yell out as they swam over my shoulder into the very edge of my vision.

Serene Green.
The emerald green water made the silhouettes look eerie and stunning. The chamber is like a huge bowl with nooks and crevices where the larger cat fish rest. The intricate design of the walls and stone features as your torch illuminated each part was like reading history and gave me a great respect for the slow but powerful force of nature. It was easy to see why this site is called red cave as the walls are streaked with seams of red that contrasted with the brilliant white of the limestone.
The water was crystal clear so visibility was not an issue unless a careless fin kick disturbed the dead leaves and vegatation matter on lying on the bottom. Our time was up all too quickly but our bellies were rumbling and it was time to grab some food and check into the accommodation.
As the name suggests, accommodation actually floats on the lake, it’s simple but clean and in very good condition. Mosquito nets hang in the rooms but I slept without it with all the windows open to allow the cool breeze to flow through and didn’t have one bite. The environment is stunning, peaceful and relaxing and the outside world now seems very very far away. The front of your hut is just one window and the view is stunning, you can literally step off your balcony and slip into the lake – a very refreshing way to wake up.

After a lovely Thai lunch we set off to check out another location and have a little explore in preparation for the next day. We returned as the sun was setting, hungry once more. The evening meal included fresh fish, curry, omelette and rice and was some of the best Thai food I’d tasted in a while. The family who run the raft house are friendly and very accommodating and make your stay here easy. Kayaks are for rent for you to explore at your own pace and they will organise a long tail for you to visit the night safari too.
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We’d checked this out with a quick orientation dive the day before and were keen to return. This site is tucked away and hidden behind a limestone pinnacle and as you enter around it’s like being in your own private lagoon. Tam Krong means temple but I think cathedral would more aptly describe this huge area. As I’m swimming around I’m trying to imagine what might have lived in the cave before the damming, whatever it was it would surely have had an eagled eyed view of all surrounding it :- certainly a penthouse suite.
Many beautiful limestone columns, stalagmites and stalactites feature in this dive and the spectral green glow flows through wide fissures and windows around me reminding me of ancient ruins cloaked in mist.
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We loved this trip and have repeated it many times and we think you will love it too. We are now offering trips to this area. If you fancy something a little different, want to experience fresh water diving and enjoy a peaceful and relaxing time away from the world at large, have a look, here, at what we have put together.


















