Trail of the unexpected: Ice diving

Discover a world seen only by the lucky few beneath the frozen Lac de Tignes. Anthony Buchanan takes the plunge in search of adventure

Do you remember the scene from Omen II where the boy gets trapped under the ice? Well that gave a generation of people like me an undying fear of frozen lakes and drowning. So when I accepted an offer to go ice diving on a bright, sunny day in the French resort of Val d'Isère-Tignes in March, I was clearly in denial. And anyway, who goes diving here? Skiing, yes. But diving?

Being shown how to don a diving mask while wearing ski gear is an odd experience, but our trainers, Pierre and Davide from the Evolution 2 ski school, helped put us at ease. No diving qualifications are needed for the experience and the whole induction process took just a few minutes. So the realisation of what was happening really only dawned after we had donned dry suits over our thermals in the little hut by the shore of the Lac de Tignes and were lying like beached seals beside a hole in the ice.

Davide dipped a flipper in the water and let out a yelp. "Oh no, it's too cold!" he joked. But although you can feel the temperature drop as you descend, I never felt cold. My only problem, in my newly buoyant state, was keeping myself upright. I felt like an astronaut who had discovered that, without gravity, moving in any particular direction is actually quite difficult. I made lots of extravagant gestures with my arms and legs to little avail. Davide resolved the problem by wrapping his legs around mine to lead me around the sights – in this mystical world such intimacy didn't appear unnatural.

Down in the deep, you might see the odd trout if you're lucky, but the main attraction is looking up at the ice overhead.

The light changes according to snow conditions. When it is snowing it is an eerie blue, when it is sunny you can see the shafts of light coming down from the various safety holes (all linked by ropes). You can even dive at night, should the mood take you.

Waving his hand in circles, Davide showed me how to create beautiful whirlpools. Then he took me to an area where the ice had frozen in two layers: in between an ever-moving sea of bubbles whirled above us. At one point we even found ourselves in an air pocket; I had to resist the temptation to take the regulator out of my mouth.

And then I was hauled out and flopped onto the ice like a stranded seal once more. Scarcely an hour after I'd taken them off I was back on my skis, my underwater adventure disappearing behind me as I headed upwards towards the high slopes once more.

The writer travelled with Crystal Finest (0871 971 0364; crystalfinest.co.uk ), which offers a week's half board, including drinks, at the Chalet Le Thorvex in Val d'Isère from £955 per person, including Eurostar return tickets and transfers. Ice diving costs €75 by day and €95 by night. See evolution2.com or tignesplongee.com for more details.