Most of the Black Cuillin rock is gabbro, a rough grey stuff that tears the skin but grips well. Intersecting it is blocky basalt, with smooth surfaces and a peach hue intensified by orange lichens. These visual charms, however, belie its treachery, for it becomes fiendishly slick when wet. The Inaccessible Pinnacle is basalt too and, when we arrive, is fogged and damp. I love mountains and enjoy a bit of scrambling, but I’m not a climber. I’m also not ticking a list, so I don’t have to do this. But in the company of fine companions, an expert guide and ropes, it feels like a once-in-a-lifetime opportunity.