Trail Ulldeter is a trail running series held in June in Camprodon, Girona province, Spain. Its races are designed for mountain terrain, not road speed. The event provides multiple distance choices, including short courses of about 10 or 11.5 km, mid-distance races of around 20 or 24 km, and longer mountain routes up to 44 or 50 km. This allows both novice trail runners and seasoned mountain racers to select suitable options.
The courses traverse the Capçaleres del Ter i el Freser natural park, ascending from mid-mountain trails towards the prominent peaks near Camprodon. Certain segments exceed 2,400 meters in elevation, demanding strong mountain fitness and fundamental trail running skills for the more challenging routes. Klassmark, the organizer, seeks out appealing, less-traveled paths that highlight the local landscape, attracting runners who seek more than a standard marked course.