OTT Marathon

Event overview

The OTT Marathon & 10 Mile Race takes place on 16 May 2026 at Parkwood Dolygaer, Merthyr Tydfil, CF48 2UR. The event offers two distances:

• Marathon - approximately 26.2 miles
• 10 Mile race

Minimum age to enter is 18. Entries open 27 July 2025 and close 9 May 2026. Entry fees are listed separately for members and non-members for each distance. The entry list shows 3 participants so far. Finishers receive a coaster and a buff.

Course and checkpoints

Both races are based in the Brecon Beacons on a looped course starting and finishing at Parkwood Dolygaer. The marathon route passes Pen Y Fan from Graig Fan Ddu, then Fan Y Big, then Talybont Reservoir and the final climb up Tor y Foel. The 10 mile follows the marathon route to Checkpoint 1, then returns to Dolygaer on forestry tracks.

The marathon has three checkpoints: at 7.0 miles, 14.5 miles and 20.5 miles. The 10 mile has one checkpoint at 7.0 miles. There is a cutoff for the marathon at 20.5 miles set at six hours from the start. Aid stations include food and cakes.

Mandatory equipment

The organiser lists compulsory kit for the marathon and for the 10 mile race. Marathon requirements include a charged mobile phone, minimum 1 liter 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 with a reusable cup. The 10 mile compulsory items include a first aid kit, bivvy or foil blanket, 500 ml water, waterproof jacket and a reusable cup. Visit the organization's website for the most recent information.