Chiltern Hills 100K
Chesham, United Kingdom • 9 May 2026
Chiltern Hills 100K
The Chiltern Hills 100K is an ultra marathon taking place on 9 May 2026. The event base is the Guide Hut in Chesham, Buckinghamshire. The route is a 100-kilometre, anticlockwise loop on trails through the Chiltern Hills. It features approximately 1800 metres of elevation gain. Key landmarks along the way include the Ashridge Estate, Coombe Hill, Whiteleaf, Bledlow Ridge, and Great Hampden.
The time limit is 18 hours. The race is limited to 250 participants, and the minimum age is 20. Entry costs £152 (or £150 for UKA-affiliated runners). Registration closes on 22 April 2026 at 17:00. The event is a UTMB World Series Index Race and is licensed by the TRA under UKA rules.
Participants must carry mandatory gear, including a mobile phone, navigation device with the route GPX, a hydration system, waterproof jacket, spare warm layers, a head torch, a reusable cup, basic first aid supplies, and cash or a bank card. The course is fully marked, and GPS tracking is provided. There are six aid stations offering water, Coke, electrolyte drinks, gels, chews, crisps, sweets, sandwiches, flapjacks, and fruit. A drop bag is available at the 41.4-kilometre checkpoint. Post-race food is included. Visit the organization's website for the most recent information.