Pegasus - The RIDUM

Caerphilly, United Kingdom • 5 Sep 2026

The Rhymney Valley Ridgeway Ultra Marathon

The RIDUM is a 30 mile ultra marathon that follows the Rhymney Valley Ridgeway Walk in South East Wales. The course begins and ends at Parc Penalta, taking participants along the ridge tops of the Caerphilly basin. The route consists of approximately 90% trail and 10% road, featuring a total elevation gain of about 4,402 feet.

The event follows a waymarked circular path that encircles the River Rhymney. Runners pass through various landscapes including woodland, lanes, and open trails. A notable point on the course is Mynydd Machen, a hill reaching 362 metres in height, which serves as the highest point of the trail.

Organizers provide two fully stocked checkpoints along the route. These stations offer snacks, fresh fruit, drinks, and seating. To participate, runners must carry specific mandatory equipment, including a water carrier, a mobile phone, a head lamp, a foil blanket, and a waterproof jacket. The event does not enforce strict time limits, focusing instead on supporting all participants to complete the course.

Available distances: Visit the organization's website for the most recent information.

  • 30 miles
  • 15 miles

Race information

30 mi
The Ridum 2026 Ultra
15 mi
The Ridum Half 2026
Visit the organization's website for the most recent information.
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