Chiltern Hills 100K

Chiltern Hills 100K is a TRA-licensed 100-kilometer ultramarathon staged in the Chiltern Hills, with base at Chesham Guides Headquarters in Chesham, Buckinghamshire. The anticlockwise loop traverses popular trails and iconic landmarks such as the Ashridge Estate, Coombe Hill, Whiteleaf, and Bledlow Ridge, following The Ridgeway and wrapping through Tring Park, Wendover and Hampden before finishing back in Chesham. The course features six aid checkpoints, marked navigation plus GPS tracking, and a fully marshalled, marked route within a 18-hour time limit.

Entry is about £152, open to runners 20+, with medals, post-race meal, photos, drop bags, and UTMB-World Series affiliated status. Visit the organization's website for the most recent information.