End of season 50 km looped challenge in some of the Chilterns finest countryside, with historic trails, rolling hills, nature reserves, and fantastic views. At our basecamp in Henley, there’s a Saturday night celebration BBQ, bar & entertainment, with extensive on-site camping & parking options. A route with real variety and some wonderful scenery – and easily accessible from London. You’ll get full support & hospitality, and with 25 km loop option and a 10K loop also available, there’s a Chiltern Ultra Challenge® for everyone!