THE ULTIMATE ENDURANCE EVENT
Find out more and enter at thenorthumbrian.com
The Northumbrian is the ultimate endurance test, open to individuals and teams seeking to conquer the beautiful waters, forests and terrain that give Northumberland and Kielder its unique character. The challenge takes stamina, determination, grit and endurance to complete, but there is no better reward, and no better setting to explore.
The 2026 Northumbrian weekend was not only the biggest event yet, but also the host of the 2026 British and English Middle Distance Triathlon Championships. The 28K and 50K UTMB Index Trail Runs moved to Saturday to accommodate growing numbers, while the Full Iron Distance Triathlon tested the bravest athletes alongside the Half Iron Distance and Aquabike on Sunday.
SUNDAY: A half iron distance triathlon and aquabike (swim & bike) in and around the stunning and challenging Kielder Water and Forest.
SWIM
- 1.2 miles in the breath-taking serenity of the famous Kielder Water
BIKE
- 56 miles through the stunning valley and a raid over the Border to conquer the challenging, inspiring roads
RUN
- 13.1 miles along the infamous Forest trails that host the testing Kielder Marathon
SATURDAY: UTMB INDEX ULTRA TRAIL RUNS:
50K Ultra Trail Run
- 48km run with +700m elevation
28K Trail Run
- 27km run with +400m elevation
Included in your entry fee:
- The Northumbrian Cycling Jersey / Running T-shirt (individual entries only)
- Swim Cap
- Electronic Chip Timing
- On Course Support
- On Course Nutrition
- Medal and Finisher’s Goody bag
- Parking
