The race takes place on the Cornwall coast, at the south-western tip of England. The route follows the coast path, a succession of cliffs, coves, beaches and muddy ground, with long flights of steps and technical footing. In late January, wind, rain and many hours of darkness are part of the event.
Arc of Attrition by UTMB
The Arc of Attrition by UTMB is a winter ultra run along the Cornwall coast path in England. 1 km to 173 km, and the event is part of the UTMB World Series.
Prepare for Arc of Attrition
A plan built from your answers and your race date.
The formats
4 formats on the program.
| Format | Distance | Vertical gain |
|---|---|---|
| Arc 100M | 107 mi | 5,507 m |
| Arc 100K | 51.4 mi | 2,708 m |
| Arc 50K | 30.7 mi | 1,458 m |
| Arc 20K | 13.7 mi | 744 m |
Organizer information, checked on September 21, 2026 · arcofattrition.utmb.world
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 August 3, 2026 and October 26, 2026.
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.
When to start
August 3, 2026
→ October 26, 2026
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 Arc of Attrition by UTMB in 2027?
Arc of Attrition by UTMB is run on Friday, January 22, 2027 in Cornish coast. Date published by the organizer, checked on September 21, 2026.
Is the Arc of Attrition course hard?
Yes. The coast path strings together short steep climbs, steps and mud, in daylight and in the dark. Winter weather on an exposed coastline adds cold and wind, which makes the longer formats particularly demanding.
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.
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
Richmond → Oxford · United KingdomUltra
Centurion Thames Path 100
May 1
It follows the Thames towpath throughout and carries a 30-hour cut-off.
Your race is not here?
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