OTT Marathon

Dol-y-Gaer, United Kingdom • 16 May 2026

Event details

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 - about 26.2 miles
  • 10 Mile - 10 miles

Minimum age is 18 or older. Entries open 27 July 2025 and close 9 May 2026. Entry fees listed are:

  • UKA Member - Marathon £55.00; Non Member - Marathon £57.00
  • UKA Member - 10 Miles £24.00; Non Member - 10 Miles £26.00

All finishers receive an OTT Trail Marathon coaster and a buff.

Course, checkpoints and compulsory kit

The marathon is a looped trail route in the Brecon Beacons. The route takes in Pen Y Fan from Graig Fan Ddu, then Fan Y Big, then heads toward Talybont Reservoir and the final climb up Tor y Foel. The 10 mile route follows the marathon route until Checkpoint 1, then returns to Dolygaer via forestry tracks.

Checkpoints:

  • Checkpoint 1 at 7 miles (both races)
  • Checkpoint 2 at 14.5 miles (marathon only)
  • Checkpoint 3 at 20.5 miles (marathon only)

There is a 6-hour cutoff for the marathon at Checkpoint 3 (20.5 miles). Compulsory kit for the marathon includes a mobile phone (fully charged), minimum 1 litre hydration, foil blanket or bivi bag, 400 kcal emergency rations, basic first aid kit, head torch or torch, compass, whistle, waterproof jacket and trousers (Tapped seems), warm layer, hat and gloves, and a bag/rucksack and reusable cup. Compulsory kit for the 10 mile race includes a first aid kit, bivvy/foil blanket, 500 ml water, waterproof jacket and reusable cup. Visit the organization's website for the most recent information.

Race information

26 mi
Ott Marathon - 26.2 (ish) Miles
10 mi
10 Mile Race
Visit the organization's website for the most recent information.
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