Chiltern Hills 100K
Chesham, United Kingdom • 9 May 2026
The Chiltern Hills 100K is a 100-kilometer ultra marathon held in the Chiltern Hills, starting and finishing in Chesham, Buckinghamshire. The race features an anticlockwise loop passing notable landmarks such as Ashridge Estate, Coombe Hill, and Bledlow Ridge, incorporating sections of The Ridgeway, Chiltern Way, and South Bucks Way trails. With over 1800 meters of elevation gain, the course is fully marked and supported by six aid stations offering hydration, nutrition, and restrooms. The event is limited to 250 runners aged 20 and above, includes GPS tracking, chip timing, and medical support, and is organized under UK Athletics and Trail Running Association rules. Post-race food and a finisher’s medal are provided. Visit the organization's website for the most recent information.