Originally from the Vosges region of France, Guillaume Pierrel was born on skis. He started Nordic skiing at the age of two and made his first ascent to 2500m (with 1500m of elevation gain) at the age of four. He then went on to ski at a high level and won the title of French Team Vice-Champion in 1997 in Autrans, France. Destined to become one with these white gold-covered peaks, he then took up freestyle and derby skiing in 2003, accumulating race numbers and enjoying the competition, and became a ski instructor in 2008.

Today, Guillaume is a mountain guide in the emblematic French resort of Chamonix and has led several ski expeditions abroad, notably solo in Bolivia and Peru, on peaks of over 6000m. Born from a passion for the mountains, Guillaume has dedicated his life to skiing, but also to ultra trail and mountaineering: in 2019, he ran the Sky Running on Lenin Peak, in Tajikistan, the highest race in the world culminating at 7134m. On his return, he completed the UTMB in 27 hours. Thirsty for discovery and adventure, Guillaume left for an expedition to Pakistan in 2021, and made this area his new playground, with its peaks counted among the highest in the world. Putting his skis at more than 8000m, in alpine style and without oxygen was a summit he had ever dreamt to reach, and the consecration of many years of hard work and training.