The Brutal Extreme Triathlons

Llanberis, United Kingdom • 19-22 Sep 2026

Event overview

The Brutal Extreme Triathlons take place in Llanberis, North Wales, from 19 to 22 September 2026. The event starts with a lake swim in Llyn Padarn, continues with laps on a 28 mile bike circuit that includes the climb over Pen y Pass, and finishes with lake laps plus a mountain section on Yr Wyddfa (Snowdon) via the Llanberis Path. Entries are limited to athletes aged 18 and over on race day. Relay teams of 2 to 4 members are allowed and must change the timing chip at the main HQ marquee.

Distances and course

Distances are offered as solo or team relay in the following options:

  • Half (Canol): 2 bike laps (56 miles), 2 swim laps, 1 lake run lap (5 miles) plus the mountain section
  • Full (Mawr): 4 bike laps (112 miles), 4 swim laps, 3 lake run laps (15 miles) plus the mountain section
  • Double (Cawr) and Triple (Goron): multiple laps for ultra distances; mountain section and lap order differs for safety

The bike lap is 28 miles on open roads. The lake run lap is 5 miles. The mountain section follows the Llanberis Path and is approximately 9 miles up and down.

Support, kit and rules

Support crews are required for the Double and Triple events and must attend the race briefing for those races. Support crews must not follow athletes closely on the bike - they should use lay-bys or car parks - and must stay near the athlete on the mountain. A kit list is required for all athletes and includes a waterproof map, compass, whistle, waterproof coat and trousers, warm clothing, gloves, hat, nutrition, a charged waterproof mobile phone, survival foil, and blister kit. Specific items required for some distances include a head torch and a red tail light or glow sticks. On the bike, a hi-viz vest must be worn at all times; helmets are mandatory and drafting is not allowed. Trophies are awarded to the first three male and female finishers in each race. Visit the organization's website for the most recent information.

Race information

Visit the organization's website for the most recent information.
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