A 100 mile ultramarathon along the South Downs Way National Trail from Winchester to Eastbourne. The route follows chalk ridgeway across open downland with sustained rolling elevation rather than steep mountain climbs. Surfaces are predominantly firm trail and grass paths, which can become slippery in wet conditions. The course is fully marked with aid stations positioned at intervals along the route.

• Other races at the same event:
South Downs Way 100K Ultramarathon
South Downs Way 50K Ultra Marathon