The Relentless

Tondu, United Kingdom • 18-20 Sep 2026

Event

The Relentless is 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. Entries open 12 October 2025 and close 17 September 2026. Registration for the event is handled through the SiEntries system.

Distances

  • 50 mile : 5 loops of a 10-mile course; 25 entrants only.
  • 100 mile : 10 loops of a 10-mile course; 25 entrants only.

Race format and logistics

The course is a 10-mile loop. Approximate total elevation is 3500 ft for the 50-mile option and 7000 ft for the 100-mile option. Time limits are 24 hours for the 50-mile distance and 45 hours for the 100-mile distance. A major hub at the start/finish acts as the lap checkpoint. The hub provides food, hydration, and medical support. Drop-bag access and a crew zone are available each lap. A sleep station is available if required.

Entries and awards

Entry fees are: 50 mile entry only £70; 50 mile entry + T-shirt £100; 100 mile entry only £140; 100 mile entry + T-shirt £170. Awards include bespoke medals and bespoke trophies for 1st, 2nd and 3rd male and female in each distance. The 100-mile finish also includes a commemorative 100-mile ring. Visit the organization's website for the most recent information.

Race information

100 mi
100 Miles
50 mi
50 Miles
Visit the organization's website for the most recent information.
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