Sirona 100

AUG
14-16
2027
Coastal ultramarathons on the Wales Coast Path offering 100 km and 100 mile options with marked checkpoints, significant elevation, mandatory safety kit, drop bags and live tracking.
14-16 Aug 2027
100 miles 100 kilometers

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Sirona 100

Sirona 100 runs along the Wales Coast Path and offers two distance options that follow coastal trails, local paths and country lanes. The course includes varied terrain with sustained climbs and descents, and coastal views along much of the route. Surface breakdown is approximately 80% trail and 20% road.

  • 100 mile: Barmouth to Mwnt; 15,000 ft elevation; 8 aid stations.
  • 100 km: Machynlleth to Mwnt; 10,000 ft elevation; 5 aid stations.

Checkpoints provide food, drinks and first aid, and designated sleep stations are available at specific checkpoints. Food and drink are served cupless, so runners must carry a reusable cup. The route is marked between checkpoints but runners must download the GPX file to a watch or GPS device; navigation skills are important in remote or variable sections.

All participants must carry mandatory safety and self-sufficiency kit. Required items include trail shoes suitable for the terrain, waterproofs and warm layers, night lighting with backup, a GPS device with the course loaded, a mobile phone, a reusable cup, a survival bag, food for several hours between checkpoints, and a first aid and blister kit. One drop bag is permitted per runner (maximum 120 L / 20 kg) and will be transported between checkpoints.

Crew and pacers are allowed at specified locations subject to access and parking limits. Live tracking is provided so progress can be followed online. Cut-off limits apply: the 100 mile event has a 50 hour cut-off and the 100 km event has a 30 hour cut-off. Visit the organization's website for the most recent information.

100 mi
100 Mile
100 km
100km

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