A trail runner on a grassy ridge above a sea of clouds

Centurion South Downs Way 100

The Centurion South Downs Way 100 follows the South Downs Way from Winchester in Hampshire to Eastbourne in Sussex.

Prepare for Centurion South Downs Way 100

A plan built from your answers and your race date.

trail training plan

The Centurion South Downs Way 100 follows the South Downs Way from Winchester in Hampshire to Eastbourne in Sussex. The route runs along the chalk ridges of southern England: broad tracks, open grassland, little in the way of technical ground, but a relentless succession of climbs and fast descents.

There is a single format of 100 miles, meaning 161km with 3,800m of ascent, with 600 starters expected. 30am. Twelve aid stations line the route and the cut-off is 30 hours, which leaves room to walk the climbs without falling behind, provided you keep moving steadily.

The formats

One format only.

Format	Distance	Vertical gain
100 miles	100 mi	3,800 m

Organizer information, checked on September 21, 2026 · centurionrunning.com

When to start

A build for this distance usually runs 12 to 24 weeks. Counted back from race day, that puts the start somewhere between December 21, 2026 and March 15, 2027.

These ranges are working conventions, not a research finding — no trial has compared plan lengths against each other. What matters more is that the plan was built for the weeks you actually have, rather than shrunk down from a longer one.

How to choose your start date

When to start

December 21, 2026

→ March 15, 2027

Worth reading before you enter

Races and distances Trail distances: what changes off the road Distance stops being the useful number. What decides a trail race is how long you are out, how much you climb, and how much the descents have wrecked your legs by the end. Read Training Eating and drinking: what’s proven, what isn’t This is where confident advice most often runs ahead of the evidence. Some of it is well tested. Some is opinion wearing a number. And one common habit can kill you. Read Races and distances When to start preparing your race Most plans fail before the first session, because the block started too late and everything had to be squeezed. Counting back from the date is the dullest and most useful thing you will do. Read

Questions

What is the date of Centurion South Downs Way 100 in 2027?

Centurion South Downs Way 100 is run on Saturday, June 12, 2027 from Winchester to Eastbourne. Date published by the organizer, checked on September 21, 2026.

What is the South Downs Way 100 cut-off?

The cut-off is 30 hours to cover 161km with 3,800m of ascent. Twelve aid stations are spread along the route between Winchester and Eastbourne, and 600 starters are expected on the line.

Is the South Downs Way 100 a hard 100 miler?

The chalk South Downs going is runnable and not technical. The difficulty lies in the 161km distance, 3,800m of climbing in repeated short pulls, and a full night of running for most of the field.

Other races

This list keeps growing; it draws no line. A race that is missing is prepared for in exactly the same way.

Edale → Kirk Yetholm (Pennine Way) · United KingdomUltra Montane Winter Spine Jan 9 The full race covers 431km, with shorter Challenger and Sprint formats alongside it. Cornish coast · United KingdomUltra Arc of Attrition by UTMB Jan 22 The Arc of Attrition by UTMB is a winter ultra run along the Cornwall coast path in England. 1 km to 173 Worthing → Eastbourne · United KingdomUltra Centurion South Downs Way 50 Apr 10 The Centurion South Downs Way 50 covers the eastern half of the South Downs Way in Sussex, from Worthing Your race is not here? Tell us about your race You can prepare for it all the same. Any race, anywhere, and even a goal without a race.

Your race is on the calendar. Your plan should be too.

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