St Kilda has been described as ‘the best scenic diving in Northern European waters" and, along with Scapa Flow, the only diving of international importance in the UK". I’d also had glowing personal recommendations from friends who had dived there, and that’s what finally convinced me to check it out for myself. The rest of the Hebrides was a bonus.

St Kilda is renowned for its adventurous diving; in particular its caves and tunnels, but I find them unexceptional places, devoid of marine life, What attracts me are the opportunities for photographing an undisturbed natural world.

The diving is very scenic; rock walls with vertical drop-offs (to 200 metres in places), huge boulders the size of houses, caverns, caves, tunnels, multi-coloured anemones and large mammals such as pilot whales. Having originated in the Gulf Stream and being oceanic the water is not green (like everywhere else in the UK) but translucent blue!

What UK wall diving lacks in glamour, it makes up for in rugged appeal. The best UK wall dives are, of course, the hardest to get at.

These mid-oceanic waters are famed for good vis and prolific marine life. Unfortunately, my visit coincided with a plankton bloom, so the expected 30m viz did not materialise. You needed to reach 30m to clear the kelp, itself evidence that light was able to penetrate that deep.

All comparisons with South Coast diving are futile. There is so much life everywhere that it’s a photographer’s dream. No commercial fishing takes place on any kind of scale here and practically every dive presents you with a unique sight.

On one occasion I counted thirty huge, edible crabs, living in a shallow fissure running up a rock wall. One diver picked up so many seven-pound lobsters and crays on that same dive that he had difficulty staying on the surface, even with a fully inflated drysuit and stabbie.

I had many memorable dives whilst there, but arguably the best was with four seals, one of which became so inquisitive that my buddy and I got within a metre of her. She then played tag and at one stage even tried to nibble my fins!

The overwhelming impression I had of seals was their intelligence. I had the suspicion that their expression denoted bewilderment at the way these diver creatures, dressed up like Christmas trees, moved so awkwardly.

We tried to persuade one to do forward and backward rolls but it viewed us with indifference. We marvelled at this creature’s air endurance as we hung on our delayed SMB line doing a decompression stop. The seal was still on the bottom after half an hour on one breath, whilst we were heading to the surface after the same time and a whole tank.

There is absolutely nothing to do on the Islands between dives. The only life there are a few sheep and an army radar tracking station. National Trust work parties come in the summer to play with the puffins. After two weeks there I was well ready to steam into a Pizza Hut! There is also a pub - the Puff Inn. It’s part of the army barracks and visitors are welcome.

They’ve also got some weather up there. On average it’s five degrees colder (air and sea) than in Southern England, and there are either sea fogs or gale-force winds to contend with. Spending 24 hours strapped in your bunk is no fun, I can tell you! A trip up there is definitely an expedition, not a holiday.

So, does St Kilda live up to its reputation as the best UK diving location? I would not be so foolish as to make such a subjective judgement. After all, you can have an incredible dive a lot nearer home, and in unlikely locations.

It’s horses for courses, from a photographer’s point of view. I don’t think is worth the extra effort and expense over and above other locations in Scotland; but will say this - you would be hard pushed to find more adventurous diving

The techniques for wall diving in temperate waters such as those at St Kilda dictate a higher degree of personal preparation and discipline than for tropical walls or, for that matter, the average UK club dive; this is mainly because of the remote location.

It was my first experience of adventurous diving and I was indebted to the other members of my party for the advice they gave me.

St Kilda is not for novices. Basic skills, such as buoyancy control, adequate monitoring of depth, time, and buddy should have already been mastered.

Staying well within the limits of your tables (or computer) is recommended as the nearest recompression chamber is back on the mainland.

It is advisable from a decompression point of view to avoid square profile dives -descending to your maximum depth and remaining there for the duration of the dive. Instead, work your way up gradually, and from early on in the dive. That’s what walls were made for and there’s always something of interest at any depth to keep you amused.

Decompression computers come into their own on variable profile wall dives, updating no-stop times as you work your way back up. Remember: don’t re-descend in mid - dive.

Walls provide the diver with a natural reference point, making control of the

ascent rate easier. Don’t forget this is especially important as you approach the surface.

Photography and text by  Benny Sutton