The Relentless

Tondu, United Kingdom • 18 Sep 2026

Event overview

The Relentless is an ultra running event scheduled for 18 September 2026 at Bridgend Miniature Railway, Fountain Road, Aberkenfig, Tondu, Bridgend CF32 0EH, Mid Glamorgan, UK. The event is organised by Mad Running Junkies. Each distance is limited to 25 entrants. Entries open 12 October 2025 and close 17 September 2026. Entry fees are listed per distance and include options with or without a T-shirt: 50 mile - £70 (entry only) or £100 (entry + T-shirt); 100 mile - £140 (entry only) or £170 (entry + T-shirt).

Course, format and support

The course is a 10-mile loop used repeatedly to reach the event distances:

  • 50 mile - 5 loops, approx 3500 ft elevation
  • 100 mile - 10 loops, approx 7000 ft elevation

Runners complete repeated 10-mile segments. Aid provision is concentrated at the start/finish hub which also serves as the lap checkpoint. The hub offers food, hydration, and medical support, plus drop-bag access, a crew zone each lap, and a sleep station if required. Time limits for the event are 24 hours for the 50 mile and 45 hours for the 100 mile. Visit the organization's website for the most recent information.

Race information

100 mi
7000 m+
100 Miles
50 mi
3500 m+
50 Miles
Visit the organization's website for the most recent information.
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