Backyard Ultra Curillas - El Último Arriero 2026

Backyard Ultra Curillas - El Ultimo Arriero is a last-runner-standing ultramarathon in Curillas, within the Montana Leonesa. Each hour, runners complete a 6.706 km lap. When the bell rings again, anyone not back in time is eliminated, and the race continues until only one runner can start and finish another lap. The format is straightforward to grasp yet difficult to endure, as there is no set finish distance, and strong runners may exceed 200 km. The loop crosses forest tracks and technical trails, featuring approximately 70 meters of elevation gain per lap. This repeated exertion accumulates rapidly. Weather conditions can intensify the race difficulty, and the mental aspect is as crucial as physical speed, requiring runners to reset each hour and decide to continue. Reports indicate solid organization, clear course marking, available showers and restrooms, ample free water, and aid stations that varied between laps. One participant noted additional aid on every lap up to the 30th. Comments also suggest a small event with dedicated early supporters, including participants hoping for its return in future editions.