The 100 Km dei Forti is a mountain bike race in Trentino, centered on challenging off-road riding across the Alpe Cimbra. Participants can choose from a 94.4 km Marathon course with 2,635 m of elevation gain, a 52.4 km Classic course with 1,300 m, or a 36.2 km Nosellari Bike route that includes 1,006 m of elevation gain. The event spans two days and attracts over 1,500 participants annually, including professional athletes, dedicated MTB riders, families, and young cyclists.
The routes traverse dirt roads and historic World War I military paths, combining long climbs, descents, dust, and historical remnants. Riders will pass trenches and the ruins of seven war forts, lending the course a distinct character compared to typical mountain bike marathons. The Marathon and Classic routes serve as tests of strength and endurance, while the Nosellari Bike offers a shorter, yet still demanding, ride preceding the main events. Now in its 30th edition, the series holds a significant place in the local MTB schedule.