The prestigious Ultra-Trail du Mont-Blanc (UTMB) commenced on Friday, drawing 2,500 runners to the iconic mountain range. The event, a highlight of the ultra-running calendar, is experiencing growing popularity, attracting a larger number of participants annually. However, this surge in runners is prompting increased concern among local residents regarding the race’s environmental footprint. The UTMB week’s flagship race faces scrutiny over its impact on the fragile alpine ecosystem. Organizers are under pressure to balance the event’s success with sustainable practices. This year’s start marks a critical point in addressing these ecological challenges alongside athletic competition. The future of the UTMB may depend on demonstrable commitment to environmental protection.