The Northumbrian

THE ULTIMATE ENDURANCE EVENT

Find out more and enter at thenorthumbrian.com

The ultimate endurance test will be open to a limited number of individuals and teams to conquer the beautiful waters, forests and terrain that give Northumberland and Kielder its unique character. Combining scenery, adventure, stamina and determination, the Northumbrian is for those seeking a challenge, and an outstanding setting to explore. 28th June 2026 will be the 5th anniversary of the full and half iron distance triathlons, and joined again by the 20K and 50K UTMB index ultra trail runs.

A full and half iron distance triathlon in and around the stunning and challenging Kielder Water and Forest.

• SWIM

  • 2.4/1.2 miles in the breath-taking serenity of the famous Kielder Water

• BIKE

  • 112/56 miles through the stunning valley and a raid over the Border to conquer the challenging, inspiring roads

• RUN

  • 26.2/13.1 miles along the infamous Forest trails that host the testing Kielder Marathon

UTMB INDEX ULTRA TRAIL RUNS:

• 50K Ultra Trail Run

  • 48km run with +700m elevation

• 20K Trail Run

  • 27km run with +400m elevation

Included in your entry fee:

• The Northumbrian Cycling Jersey / Running T-shirt (individual entries only)
• Swim Cap (triathlon only)
• Electronic Chip Timing
• On Course Support
• On Course Nutrition
• Medal and Finisher’s Goody bag
• Parking