Chiltern Hills 100K
The Chiltern Hills 100K is an ultramarathon set to take place on 2 October 2027 (TBC). The event is based at Chesham Guides HQ, Buckinghamshire (HP5 1HX), and follows an anticlockwise loop around trails in the Chiltern Hills. The route distance is 100K with over 1800 m of elevation gain and a time limit of 19 hours.
The course passes a number of named landmarks and areas, including the Ashridge Estate, The Ridgeway (Ivinghoe Beacon to Aldbury), Tring Park, Wendover, Coombe Hill, Whiteleaf Hill, Bledlow Ridge and Great Hampden, before returning to Chesham. The route is fully marked and uses open GPS tracking. A GPX file and printable map are available, and a runner's guide and spectator guide are provided by the organiser.
Checkpoint and aid station locations include Hastoe Village Hall (14KM and 41.4KM), Little Gaddesden Village Hall (28KM), Whiteleaf Hill (57.8KM), Bledlow Ridge Village Hall (75.3KM) and Little Hampden (88KM). Several aid stations list toilet facilities.
The race is limited to 250 runners, has a minimum age of 20, and is licensed by the Trail Running Association under UKA rules. It is listed as a UTMB World Series Index race.
Route Description
The route starts in Chesham and follows an anticlockwise loop along some of our favorite trails in the Chilterns.
The first leg to CP1 (14K) follows the Chiltern Link trail and heads east to Hastoe. From this first checkpoint, runners complete a loop around National Trust's Ashridge Estate, via Little Gaddesden (CP2), which includes a stunning section of The Ridgeway from Ivinghoe Beacon to Aldbury.
Once back at Hastoe (CP3 - 41.4k), runners will have access to their drop bag before continuing along The Ridgeway, passing through Tring Park, Wendover, Coombe Hill, Whiteleaf Hill (CP4 - 57.8K), and along to Bledlow Ridge.
The Bledlow Ridge Village Hall checkpoint marks 75K into the race; the final leg follows a selection of woodland trails through Hampden and along to Great Missenden.
From Missenden, the end is in sight as the loop is complete, and you arrive back in Chesham.