OTT Marathon

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

OTT Marathon & 10 Mile Race

The OTT Marathon and 10 Mile Race take place in the Brecon Beacons, starting and finishing at Parkwood Dolygaer in Merthyr Tydfil. The event features two distinct distances through mountainous terrain and forest tracks.

  • Marathon: This 26.2-mile course is a mountain loop that includes significant climbs. Participants summit Pen Y Fan from Graig Fan Ddu, cross Fan Y Big, and pass the Talybont Reservoir before the final ascent of Tor y Foel.
  • 10 Miles: This shorter alternative follows the marathon route to the first checkpoint before diverging onto forestry tracks that lead back to Dolygaer.

The marathon distance includes three aid stations located at 7 miles, 14.5 miles, and 20.5 miles. The 10-mile race includes one checkpoint at the 7-mile mark. For the marathon, a cut-off time of 6 hours is enforced at the final checkpoint, requiring a physical pace of approximately 18 minutes per mile.

Participants must be at least 18 years old. Specific compulsory equipment is required for all runners, including a first aid kit, foil blanket, waterproof jacket, and a reusable cup. Marathon participants must carry additional gear such as a head torch, compass, whistle, and emergency rations. All finishers receive a themed coaster and a buff. Visit the organization's website for the most recent information.

Race information

26 mi
Marathon
10 mi
10 Mile Race
Visit the organization's website for the most recent information.
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