This April, 15 years' on from his previous (successful) attempt at a multiple marathon, Charlie is running in the 2023 edition of the Marathon des Sables .
The Marathon des Sables - often referred to as the world's toughest footrace - is a self-supported endurance event run across the Moroccan Sahara over the course of a week, through some of the world's most inhospitable terrain, covering roughly the equivalent of six marathons in seven days: approximately 250 kilometres in total.
All 'competitors' in each year's event must carry all their own food, sleeping equipment and other supplies for the week (only water is provided) and endure temperatures that regularly exceed 40C during the daytime. At night, 'competitors' hunker down, eight to a bivouac, sharing pain-induced camaraderie, freeze-dried food, a complete lack of privacy, and exceptionally basic sanitation. The completion rate for the event ranges from around 50% in 'tough' years to 90% in more benign renewals.