A 19-year-old from Basingstoke has emerged as one of Britain’s most promising athletes after completing two laps of The Berkeley Marathons, one of the nation’s toughest ultramarathon events, held in Gloucestershire over the weekend of 26th–27th September 2025.

Peter Knowles covered 55 miles of the 130-mile course, which features 15,000 feet of elevation gain. The event challenges runners to finish five marathon-distance laps within 24 hours on an unmarked route. Competitors must navigate using paper maps, solve puzzles to locate checkpoints, and carry all their supplies without any support stations.

Modelled on the Barkley Marathons in the US, the British version is intentionally designed to test human endurance to its limits. Organisers describe it as an “unfinishable race”, where anyone completing all five laps earns the rare honour of engraving their name on a ceremonial bell. No runner has yet managed to do so.

Knowles, who began running in 2024, credits much of his motivation to Jasmin Paris, the British ultrarunner who became the first woman to complete the American Barkley Marathons in March 2024. Paris finished the 100-mile course in Tennessee in 59 hours, 58 minutes, and 21 seconds, just 99 seconds before the 60-hour cut-off. Her feat has inspired a new generation of ultrarunners, including Knowles, who has already completed 16 ultramarathons since starting the sport.

Supported by natural active foot care specialist The Feets, Knowles stood out among the 69 starters this year. No other runner managed more than four laps, with one participant setting a new record for that distance. Twenty-nine competitors withdrew after just one lap, while 25 failed to complete the second. The high dropout rate highlights the physical and mental demands of the event, organised by Gert Lush Events, a Bristol-based company founded by Paul Breen to combine endurance challenges with mental health awareness and charitable goals.

Knowles described how mental resilience was key to finishing. “The hardest part was finding a reason to keep going,” he said. “When your ‘why’ fades, everything becomes harder. I had to switch off from emotion and just focus on moving forward, even when my body and mind were exhausted.”

An unexpected encounter with a horse briefly guided him along the route, but his focus never wavered. He credited The Feets’ products for helping him stay on course. “The Feets’ products made a real difference,” he said. “They’re authentic and genuinely care about what they do and I certainly wouldn’t have made it as far as I did without them.”

Logan Estop-Hall, founder of The Feets, praised Knowles’s grit. “We’re absolutely pumped to have supported Peter on this event. His determination and ability at just 19 years old is incredible and aligns perfectly with our mission to get more people active and pushing their own limits. He is certainly one to watch, and I don’t doubt with more training on trails and exposure to night navigation he can get to four, maybe even five laps. But this event is where dreams go to die, and it’s fitting that Peter’s dreams to complete the event were humbled, but his drive to reach five laps has just grown… a lot. I can’t wait to see what he does in the future.”

Knowles’s success follows other notable achievements that have earned him the nickname “Britain’s fittest teenager”. In July 2025, he ran 101 miles around a track in under 28 hours, believed to be the longest run by a British teenager. In December 2024, he won the Christmas Day Cracker Run, covering 60 kilometres in seven hours, beating 85 competitors. His first ultramarathon was a 100-kilometre Thames Path challenge in September 2024, run in honour of his grandfather battling cancer and raising funds for Cancer Research UK.

The Berkeley Marathons are held at Hamfields Leisure Centre near Berkeley Castle and include puzzle-based book collections at checkpoints, a nod to the traditions of the American event. For Knowles, the experience was life-changing. “Being the best isn’t about beating others,” he said. “It’s about being better than who you were yesterday.”

Paul Breen from Gert Lush Events said Knowles exemplifies the spirit of the race. “The race undoubtedly pushed Peter to explore his limits, and we’re confident he’s only just beginning to tap into his potential. As one of Britain’s youngest ultramarathon runners, he’s tested his limits and now has new horizons to set his sights on. We eagerly anticipate his return next year. Despite his remarkable achievement, the challenge of The Berkeley Marathons remains unconquered; the bell still awaits its first name.”

Knowles now prepares for his next challenge, a 100-mile self-supported run across the Sahara Desert in January 2026. He will carry all his gear, with water resupplies every 10 kilometres in the intense North African heat. The run will demand expert navigation, heat acclimatisation, and hydration strategy, solidifying his place among Britain’s rising ultrarunners.