Diving Khao Sok National Park, Thailand

Updated on 20th September, 2012. First published 23rd August, 2009

Khao Sok national park in southern Thailand is a reserve dominated by a 165 square kilometre lake surrounded by ancient rainforest. Huge limestone columns jut out of the water, monstrous sentinels that dwarf your longtail boat as you cruise by. Most travellers visit in order to trek through the jungle, spot wildlife and soak up the peace and tranquility that the park radiates.

I've come to see something a little different. The Pasaeng River was dammed over 25 years ago, creating the lake but putting some stunning features below the water line and it was these grottos I was here to tour. I work on Ko Tao as a scuba instructor so diving in the lake was not only going to be a great break but also very different from the colourful reef diving I do most days.

Travel around the park is only by longtail and traffic is regulated by the granting of licences to a limited number of drivers. Diving off a longtail is great fun and takes you back to how diving used to be in Thai waters: simple, relaxed and peaceful. Splashing into the green water, I look down and see a misty haze below me which doesn't bode well for the visibility beneath the lake's surface.

Once submerged and descending within only a few metres however the water becomes crystal clear. Looking at the rock formations and trees around me, it would be easy to believe that I was suspended in a fairy tale enchanted forest. Swimming around massive trees is surreal enough but the size of the stalactite that greets me beyond it is awe inspiring. The massive structure looks like an incisor and swimming passed it into the bowl shaped room behind is like entering a monsters maw.

Spooky green light illuminates the grotto which is home to curious catfish of varying size. Looking back from where I have just come the would-be teeth are now silhouetted against the emerald green water of the lake. I have well over 1,000 dives under my belt, yet I have never seen anything quite so captivating. The grotto is home to remarkable formations, with alcoves and altar-like structures and little nooks and crannies where catfish rest. I surface, very eager to explore the next site.

On the way, our longtail driver tells us about a passage that villagers used to walk through to reach a smaller lake from the main one that we are now on. The pass is now underwater and this creates some excited discussion among the divers on the boat. There is also at least one village at the bottom of the lake which has been lost to human eyes for over 25 years. Both of these are exploration projects that will be very thrilling to be a part of in the future but for now we drop overboard into the lake once more.

This site is more complex and has guidelines laid around its perimeter. Many openings pock mark the perimeter allowing ethereal light to stream in. Stalagmites and stalactites have fused to form intricate columns. A huge crazed granite wall contrasts immensely with the otherwise flowing white ghostlike features that make up the majority of the geological display. The site is a lot grander than the first. While the translation of the Thai name comes out as 'temple', cathedral is more the word that comes to my mind, but its patrons must have been gigantic.

We have plans to return to both sites the next day for more exploration but it is now time to head to our accommodation. Staying on the lake is so tranquil; raft huts offer simple yet clean rooms. The bungalow operations are family run and their restaurants offer very tasty traditional Thai food, some of the best I have tasted in a long time.

Sunset is amazing and a restful night's sleep follows. Rousing to the sound of monkeys chattering and calling in the tree tops is quite surreal yet certainly more pleasant than the growl of engines or the tooting of an alarm clock. Stepping out of my hut and into the lake is a very refreshing way to wake up and revive too. We pack the longtail for the day and head back to explore yesterday's sites further. Already the trip seems to be over too quickly and I know I will be back soon.

Whether you come for the scenery above or below water, Khao Sok is a lovely respite from the rigours of the backpacker trail and you can't fail to leave feeling rejuvenated and ready to face whatever is next.

For more information on diving in Khao Sok National Park, contact Ayesha Cantrell who can organise diving trips to Khao Sok from Ko Tao.