Our prospects of eventually graduating improved as the focus of our climbing endeavours shifted from Cambridge to North Wales. For us teenagers the iconic climb in the country lay in the Llanberis Pass, a huge open book of a feature called Cenotaph Corner. It took me four decades to muster up the courage to lead that route, but I finally managed it last year, albeit on the second attempt, following a 20ft fall at the final crux.

My first serious climb on snow and ice was with another Sidney undergrad, Ted Flint (later Brigadier Flint, Signal Officer in Chief). In the summer of 1980, we headed out to Peru, as part of a self-styled Cambridge Andean Expedition that included my brother Simon, also at Sidney. We hadn’t actually intended any proper climbing, but one volcano sort of led to another and soon we had our eyes on Huascaran, at 6,768m the highest mountain in the country and the fourth highest in the Western Hemisphere. Our local guide, Vicenti, initially scoffed at the idea of taking us up, then cried with fear (literally) and then agreed. The truth was he’d had little choice. He’d been told to take us by the local fixer, whose nickname – Pepe El Loco – spoke a thousand words. This was not a situation my mother, or girlfriend (now wife) at Homerton, would have entirely approved of. However, we made it to the top and back again, having hauled each other out of successive crevasses. Our toes were black with frost bite, but importantly still attached to our feet. I now really had the mountaineering bug!