OTT Marathon
Dol-y-Gaer, United Kingdom • 16 May 2026
Event details
The OTT Marathon and 10 Mile Race takes place on 16 May 2026 at Parkwood Dolygaer, Merthyr Tydfil (CF48 2UR). There are two distances:
- Marathon - 26.2 (ish) miles
- 10 miles
Entries open 27 July 2025 and close 9 May 2026. Minimum age is 18 or older. Entry fees are listed separately for UKA members and non-members: marathon £55 / £57, 10 miles £24 / £26. The event is organised by OTT Events Limited.
Course, checkpoints and kit
The marathon is a looped trail course in the Brecon Beacons. The route goes past Pen Y Fan from Graig Fan Ddu, up Fan Y Big, then toward Talybont Reservoir and the final climb up Tor y Foel. The 10 mile route follows the marathon route to Checkpoint 1 and then returns to Dolygaer by forestry tracks.
The marathon has three checkpoints at about 7.0, 14.5 and 20.5 miles. There is a cut off of 6 hours at 20.5 miles. The 10 mile race has one checkpoint at about 7 miles; runners must check in there. Compulsory marathon kit includes a charged mobile phone, minimum 1 litre hydration, foil blanket or bivvy, 400 kcal emergency rations, basic first aid, head torch, compass, whistle, waterproof jacket and trousers, warm layer, hat and gloves, and a bag/rucksack with a reusable cup. Compulsory 10 mile kit includes a first aid kit, bivvy/foil blanket, 500 ml water, waterproof jacket and a reusable cup. All finishers receive an OTT Trail Marathon coaster and a buff. Visit the organization's website for the most recent information.