Kielder Marathon Entry, Date & Race Guide

The Kielder Marathon is a scenic trail marathon in Northumberland, widely regarded as one of the most challenging marathons in the UK. Set within Kielder Water & Forest Park, the race offers a remote, natural route with significant elevation, making it a standout option for runners seeking a tougher alternative to flat road marathons.

The course follows forest trails and lakeside paths around Kielder Water, featuring long climbs, rolling terrain and varied surfaces throughout. While not suited to PB attempts, it delivers a rewarding endurance challenge with expansive views and a unique atmosphere in one of the UK’s most remote race locations.

Part of the wider Kielder Marathon Weekend, the event includes multiple distances and attracts runners looking for a destination-style race experience combined with a strong sense of adventure.

RaceScan tracks entry status, race date, and key race details for the Kielder Marathon in one place.