South Downs Way 100 is a 100 miles / 161km ultra marathon in Winchester, United Kingdom. Distance: 161km. Elevation: 4,000m D+. Difficulty: challenging (Challenge Rating 42/100). DNF rate: 25%. Time limit: 30h. Surface: trail. Established 2012.
South Downs Way 100
Winchester, Hampshire, United Kingdom
"100 miles along the South Downs Way. Chalk downs to the sea at Eastbourne."
A 100-miler along England's South Downs Way — chalk downs to the sea.
The Course
Point-to-point 100-miler along the South Downs Way from Winchester to Eastbourne. Rolling chalk downs with sea views on the final stretch.
hilly
point-to-point
12
Runner Experience
Solid aid station network with 12 stops along the course. Standard ultra fare — food, electrolytes, first aid.
A legendary finish line atmosphere. South Downs Way 100 is a bucket-list race with celebrations that match its reputation.
Race Day Weather
16°C
10° – 22°
65%
25%
English summer — warm, occasionally hot. Long daylight hours.
Stats & Records
2012
200
24:00:00
Entry
£150
October
days
Lore & Trivia
Centurion Running's South Downs Way 100 follows the full length of England's newest National Trail — 161km of chalk ridgeway from Winchester to Eastbourne along the South Downs. The route dates back 5,000 years as a Neolithic trading route; Iron Age hill forts dot the hilltops. The running surface is fast chalk track on exposed ridgeline, making this one of the most runnable 100-milers in the world — and therefore one where pacing errors are punished most severely. Sub-24-hour finishers are genuine athletes; the course record hovers around 14 hours.
- ▸ The South Downs Way is one of England's 16 National Trails.
- ▸ The final miles along the chalk cliffs of Beachy Head are spectacular.
- ▸ One of the UK's most popular 100-mile races, selling out in hours.
The South Downs Way is the fastest 100-miler in Britain. Which means your pacing mistakes cost you more.
Notable Editions
Sub-15 Breakthrough
The sub-15-hour barrier was broken on the South Downs Way, reflecting the escalating standard of British 100-mile running and the SDW's status as the UK's fastest 100-mile course.
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Frequently Asked Questions
How long is South Downs Way 100? +
South Downs Way 100 is a 100 miles / 161km (161km) ultra marathon with 4,000m of elevation gain. The course is point-to-point on trail terrain.
How hard is South Downs Way 100? +
South Downs Way 100 is rated challenging with a Challenge Rating of 42/100 (Challenging). The DNF rate is 25%. Runners have 30 hours to finish.
What is the weather like at South Downs Way 100? +
Average temperature is 16°C (range 10°C to 22°C) with 65% humidity and a 25% chance of rain. English summer — warm, occasionally hot. Long daylight hours.
Are crew and pacers allowed at South Downs Way 100? +
Crew access is allowed. Pacers are allowed after 80km.
What is the average finish time for South Downs Way 100? +
The average finish time is 24:00:00. About 200 runners finish each year. The DNF rate is 25%.
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