Chiltern Hills 100K

Chesham, United Kingdom • 9-10 May 2026

Chiltern Hills 100K is a TRA-licensed 100-kilometre ultramarathon organized by Runaway Racing. The next edition takes place in May 2026, starting and finishing in Chesham, Buckinghamshire, with the event base at Chesham Guides HQ in Lowndes Park. The anticlockwise route traces beloved Chilterns trails, visiting the Ashridge Estate, Coombe Hill, Whiteleaf, Bledlow Ridge, Great Hampden and stretches of The Ridgeway from Ivinghoe Beacon to Aldbury before returning to Chesham.

Runners cover about 1800m of ascent, navigate marked paths using a map and GPS, and pass six aid stations. Entry is around £150–£152; maximum 250 entrants; post-race meal provided. GPS tracking, full route marking with orange arrows; UTMB World Series Index Race. Visit the organization's website for the most recent information.

Race information

UTMB 100K
100 km
1800 m+
100k Ultra
Visit the organization's website for the most recent information.
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