About This Race
The Täby Extreme Challenge presents a distinctive 100-mile journey through the forests and trails surrounding Stockholm, Sweden. This ultra combines wide forest paths with narrower technical sections, dirt roads, and strategic asphalt stretches where runners can often find softer surfaces alongside the pavement. Despite its intimidating distance, the course maintains a relatively moderate difficulty profile with rolling hills rather than punishing climbs. The race unfolds across varied terrain that showcases the natural beauty of the Stockholm region while remaining accessible to runners without extensive technical trail experience. Standard running shoes suffice for the mostly non-technical surface, though runners should expect roots and stones on the forest sections. The 1,500 meters of elevation gain spread across 100 miles creates a challenging but manageable gradient that rewards steady pacing over explosive climbing ability. Timing in late April means runners face transitional spring conditions, with organizers noting that snow and ice should have cleared by race day. However, the pragmatic approach includes course alterations if late winter conditions persist, demonstrating the event's commitment to runner safety over rigid adherence to the planned route.
The 100-mile loop course travels primarily on wide forest trails (65% of the route) interspersed with narrower technical forest sections featuring roots and stones (12%), dirt roads (11%), and asphalt stretches (23%). Where asphalt is unavoidable, roughly half offers softer running surfaces alongside the pavement. The terrain remains largely non-technical, suitable for standard trail running shoes rather than aggressive lugged footwear.
With 1,500 meters of total elevation gain distributed across the full distance, the course presents rolling hills rather than sustained climbs. The route will be well-marked during the event, with detailed course descriptions provided on the race website prior to race day. Spring conditions in late April typically mean clear trails, though organizers maintain flexibility to alter the course if late-season snow or ice patches require safer alternatives.
Elevation Profile
The course gains 1,500m over 161km, with the steepest section between km 142–km 142.
Course Map
Route shown is approximate and for illustration purposes.
Notable Features
This Swedish ultra offers an accessible entry point into 100-mile racing with its non-technical terrain and moderate elevation profile. The race showcases the natural beauty of the Stockholm region while maintaining practical course management that adapts to spring weather conditions, making it particularly appealing to international runners seeking a European ultra experience.
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