Chiltern Hills 100K
Chesham, United Kingdom • 2 Oct 2027
Chiltern Hills 100K
The Chiltern Hills 100K is a 100 kilometre trail ultramarathon held on 9 May 2026 around the Chiltern Hills. The route is an anticlockwise loop that starts and finishes in Chesham and passes notable local landmarks including the Ashridge Estate, Ivinghoe Beacon, Coombe Hill, Whiteleaf Hill, Bledlow Ridge, Great Hampden and Great Missenden.
The course covers approximately 100K with over 1800 m of elevation gain. Navigation is fully marked and the event uses open GPS tracking. The route follows sections of The Ridgeway and includes woodland trails, ridge paths and village sections with checkpoints and support.
Aid stations are placed along the route, with key locations at Hastoe (around 14K and 41.4K), Little Gaddesden (around 28K), Whiteleaf Hill (around 57.8K), Bledlow Ridge (around 75.3K) and Little Hampden (around 88K). Some aid stations provide toilet facilities. Drop bag access is available at Hastoe on the second pass.
The event base is Chesham Guides HQ, Buckinghamshire, HP5 1HX. The race is limited to 250 runners, has a minimum age of 20 and a time limit of 18 hours. It is listed as a UTMB World Series Index Race and is licensed by the Trail Running Association under UK Athletics rules. Visit the organization's website for the most recent information.