Tenacious Ten Hour Endurance Challenge
Talgarth, United Kingdom • 9 May 2026
Tenacious Ten Hour Endurance Challenge
The Tenacious Ten Hour Endurance Challenge is an endurance running event held at Mynydd Troed in the Black Mountains of Wales. Participants navigate a 3.2 mile loop that is characterized by technical terrain and significant elevation changes. The course begins at the base of the mountain with a steep climb to the summit, followed by sections of open common trails and technical downhill paths.
Running as a loop format, the event allows participants to complete as many laps as possible within a strict 10 hour time limit. After completing the first lap in a clockwise direction, runners may choose to continue in either a clockwise or anti-clockwise direction for subsequent laps. To record a lap, participants must use a laminated card at two specific clip stations: one located at the summit trig point and another at the mountain base. Only laps completed before the final horn sounds are included in the final results.
Registration options include:
- Solo
- Pair
- Team of 4
The event provides a marked route, a medical team, and a refuel zone with food and drinks. Participants must carry mandatory safety equipment, including a waterproof jacket and trousers, a race vest with water capacity, a telephone, a hat, gloves, a first aid kit, and a foil blanket. Trail shoes are required due to the steep and technical nature of the mountain terrain. Visit the organization's website for the most recent information.