The most notorious mountain in the world – its iconic vertical mile of brittle limestone and ice, called the North Face, is the ultimate challenge for many a mountain climber. But even some of the greatest mountain climbers in the world are not prepared to take on the challenge. It’s not that it’s an impossibly difficult climb – at 1,800 m (13,000 ft) from base to the top of Face it’s not even that high. (The Eiger itself is 3970 m). It’s the commitment it entails. Once embarked on the ascent, that’s it … you need to keep going up.