Tyin Filefjell Extreme is a mountain running festival held at Tyin-Filefjell in Innlandet, Norway. The main race day is a Saturday in early September. Participants can select from three high-mountain courses: the 7.5 km Børrenøse Skyrace featuring 450 meters of elevation gain, the 21 km Tyin Filefjell Extreme half marathon with 1,050 meters of climbing, and the 53 km Tyin Filefjell Ultra, which includes 2,900 meters of ascent.
The routes traverse rugged mountain terrain, showcasing autumn colors across the hillsides and offering vistas of the Jotunheimen peaks. The shortest race is accessible for novice mountain runners, though it remains steep. The ultra distance is designed for those seeking an extended, challenging day of climbing. The event also includes activities for spectators and food enthusiasts. Participants should be prepared for mountain weather conditions, which can include snow and wind even in early autumn.