2026 Kielder Marathon - Oct 4

Single off-road loop of Kielder Water, no public roads marathon course in Kielder with 480m elevation gain. Genuinely undulating and challenging, not flat. The course circles the reservoir on the Lakeside Way with steady rises, short steep climbs and rolling forest sections throughout - roughly 480m of total ascent. Expect to run noticeably slower than your road marathon time