Skiing off piste, back country skiing, off trail skiing, call it what you will, can mean an exhilarating experience of skiing powder snow away from the crowded pistes. But in that sparkling carpet of angels poop lurk hidden dangers...

This happened some time ago in 1973.

Two men were skiing off piste in Geilo Norway in early March. The temperature was below freezing, perhaps minus 5°C, the sun was shining and eight inches of light fresh snow had fallen two nights before.

They were walking under a six foot cornice over which some of the powder snow had been blown and settled into a small back bowl. The back bowl was no wider than a couple of hundred yards with a three hundred yard slope before it bottomed out into some birch trees, but for Geilo Norway it was something out of the ordinary and something special.

The man in front continued walking under the cornice while his friend, who was about three yards behind decided he couldn’t wait any longer and started off. After three turns he stopped and the hairs on the back of his neck stood up. He knew there was something wrong with the snow although he couldn’t say what it was. It may have been that most of it was blown snow although it was reasonably light, or it may have been a hard snow base he could feel underneath. Of course it could just have been his sixth sense. Whatever it was made him stop and turn to his friend, Benni, who had now moved a few more yards under the cornice.

If it’s possible to shout ‘Benni’ quietly that’s what he did. He then put his finger to his lips, and stuck his hand up in a sign to stop. Benni stopped. The skier took his skis off and treading as carefully as possible began to walk straight back up the hill. It was only about fifteen yards.

At the very moment he reached the path under the cornice, there was a thud and the ground shook. It seemed as if the whole mountain was moving. A huge crack fifty yards long opened up just below their feet. The depth of the slab that had broken off was only eight inches deep yet it made a noise like a stampede of water buffalo. Within about five seconds the thundering stopped as the front end of the avalanche hit the upturn and the birch trees.

We both skied down on the firm base (I expect you‘ve guessed that I was Benni’s friend), and gaped at the six foot wall of snow that had piled up. It was set hard with great chunks of solid snow the size of suitcases welded into each other. We were very lucky; if we had been buried by this monster it would have already crushed the life out of us. If we had just been caught by an arm or a leg, it would have needed a spade to dig us out. If just our heads had been caught we would already have been suffocated.

This was a lesson early on in my skiing career that I have never forgotten. Of course there have been temptations since; fortunately, because of this early experience, I’ve been able to check myself or the people around me. It is tempting to go off into the great white yonder, but once again don’t be tempted to try anything you’re not sure of.

Most of the locals, who are keen skiers, will quite happily tell you whether the conditions in such and such a place are all right, or whether they should be avoided like the plague. I’m not being a spoilsport because nine times out of ten with care you will be all right, but carry awareness and caution with you all the time.

Simon Dewhurst has taught downhill skiing in North America, Scandinavia and the European Alps for 35 years. He currently runs a ski chalet agency in the French Alps. His book "Secrets of Better Skiing" can be found at http://www.ski-jungle.com. If you have any comments about the above article, he will be happy to answer them.