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."
Score Breakdown
Based on distance, vertical gain per km, terrain difficulty, weather extremes, historical DNF rate, and race format.
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.
Experience ratings are based on runner reports, race reviews, community feedback, and editorial assessment. Scenery reflects the visual quality of the course. Organization covers aid stations, logistics, and communication. Community measures the atmosphere, inclusivity, and camaraderie among runners.
Race Day Weather
16°C
10° – 22°
65%
25%
English summer — warm, occasionally hot. Long daylight hours.
Stats & Records
2012
200
24:00:00
25%
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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