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Ultras · United Kingdom · England

Arc of Attrition 100K

Arc of Attrition by UTMB 2027
Full
Entry has closed for this year. The race page shows Race full at fill time (2026-10-26). The 100M and 20K showed open registration on the event home page.
Race dateJanuary 23-24, 2027
Duration2 days
Start10:00am
Whenin 88 days

Who's going to Arc of Attrition 100K?

I'm running itPlan your weeks and your aid station times I'm crewingWhen to leave, where to park, at every stop I'm pacing or cheeringAsk your runner for their Out Here link

Free. You can start with nothing.

Official website Aid stations Notify me if this race changes
Free, and always will be. NavRun makes money from race-day planning for runners who want it, never from this. Ultras change constantly, sometimes the morning of. Always confirm with the race director and the official website before you rely on anything here.
Distance The race
82.7K
Climb Our math
6,740 ft We worked this out from what the race prints.
Descent Our math
6,621 ft We worked this out from what the race prints.
High point
not checked yet
Time limit
16:00:00
Aid stations
6
Started
not checked yet
Finished
not checked yet
Finish rate
not checked yet
The course

Where it goes point to point · 6 aid stations

Course line from the race's own GPX. Source file. Year of this file not known.

Point to point along the South West Coast Path from Land's End to Perranporth Airfield, taking in cliffs, remote headlands and the Atlantic coast heading north, with 16 hours to finish.

Cliff paths and cliff edges that can be steep and arduous. Larger aid stations are about 20 miles apart, so runners carry what they need for long stretches. The later part is run in the dark, and January weather can be cold, wet and windy.

The race

What this one is

A winter 100K on the South West Coast Path in Cornwall, point to point from Land's End to Perranporth Airfield, starting Saturday morning with 16 hours to finish.

Part of Arc of Attrition by UTMB, founded in 2015 by MudCrew in Cornwall as a winter 100 mile race, which joined the UTMB World Series in January 2025. The 2027 FAQ lists Land's End as one of the new start lines.

Getting in

Getting in Entry, lottery and what the race asks of you before race day.

Lottery
No arcofattrition.utmb.world
Lottery opens
not checked yet
Lottery draw
not checked yet
Field cap
not checked yet
Registration
UTMB arcofattrition.utmb.world
Qualifying
No UTMB Index is needed for the Arc 100K, but experience in long distance races is required and the race is not for beginners in trail running. arcofattrition.utmb.world
Minimum age
20 arcofattrition.utmb.world
Transfers
No arcofattrition.utmb.world
Deferrals
No arcofattrition.utmb.world
Crew access, pacers and drop bags

The rules that shape your day Anything marked "not checked yet" is a gap in what we hold, never a no from the race.

Crew allowed
No arcofattrition.utmb.world
Vehicles per runner
not checked yet
Pacers
No arcofattrition.utmb.world
Muling
not checked yet
Drop bags
Yes arcofattrition.utmb.world
Cupless
Yes arcofattrition.utmb.world
Course marking
Partially Marked arcofattrition.utmb.world
Night running
Yes arcofattrition.utmb.world
Dogs
Not allowed arcofattrition.utmb.world
Headphones
Allowed arcofattrition.utmb.world
Crew rules
No personal assistance (support crew) at any point along the route or during the race. Only participants may enter aid stations. The race advises having someone meet you at the finish to drive you home. arcofattrition.utmb.world
Pacer rules
not checked yet
Drop bag rules
One 30 litre UTMB World Series drop bag, handed in at the Bag Drop marquee before the coach to the start, and taken to the Lelant aid station. Collect it at the main event venue with your race bib. Only UTMB World Series drop bags can be used, and poles are not allowed in them. arcofattrition.utmb.world
Cutoff philosophy
Cut-off times are strictly enforced. They allow someone moving at an average pace to reach each aid station and the finish within the time allowance; the FAQ recommends a minimum average speed of 5.2 km per hour including stops. With wave starts, the maximum time and time barriers are counted from the last wave. arcofattrition.utmb.world
Aid stations

Every stop, and what you get there ● yes   ○ no   ? nobody has checked   – does not apply to this race

Mile Station Cutoff Crew access Bag Pacer Med To next
? Land's End
NoneSignal wrong?
 ? ? ? ? ? ?
? Pendeen
NoneSignal wrong?
 1:30pm ? ? ? ? ?
? Lelant
NoneSignal wrong?
 7:00pm ? ● ? ? ?
? Godrevy
NoneSignal wrong?
 8:30pm ? ? ? ? ?
? Portreath
NoneSignal wrong?
 11:30pm ? ? ? ? ?
? Perranporth Airfield
NoneSignal wrong?
 2:30am ? ? ? ? ?
What it looks like out there

Somebody has been out there with a camera the tables say the climb is long. these say what long feels like.

Nobody has been out there with a camera or a microphone yet. A gap means nobody has found it, not that it is not out there. Seen a course preview or a film of this one? Send us the link.

Add to this page

What you know every one of these is read by a person before it changes anything

Ran this race? Tell the next runner what you know.

Nobody sees it until we have read it. No account, no sign-in.

Leave blank if it applies to the whole race.

Leave blank if it is not about one particular stop.

Optional. Something like “Cal Street, mile 62 to 78”.

Write it the way you would say it to someone at the start line.

Optional, and it decides nothing. It only tells the next runner where this is coming from.

Optional.

Optional, and never shown on the page. Only so we can ask you a question about this note.

Leave this field blank.

See something wrong or out of date? Suggest an edit.

This changes nothing on the page on its own. Somebody checks it against the race first.

Optional. Filled in for you when you start from a specific line on the page.

Copy it as it appears, so we can find it.

The corrected value.

Required. Where it came from: the race email, the runner manual, what you saw on the day.

Optional.

Optional. A screenshot or a photo of the sign works.

Optional, and it decides nothing.

Optional.

Optional, only so we can come back to you about this correction.

Leave blank if it is about the whole race.

Leave blank if it is not about one particular stop.

Leave this field blank.

Seen a course preview or a film of this one? Send it over.

Somebody watches it before it goes anywhere near this page. What we are after is footage of this course, on the ground. If it would be just as true of any other race, it is not this.

Required. A line is plenty. Where the climbs are, what the footing does, what the last twenty miles look like.

Optional, and it decides nothing.

Optional.

Optional, and never shown on the page. Only so we can ask you a question about this one.

A YouTube link, a race report, a photo gallery, whatever it is.

Optional, and we credit them on the page.

Leave this field blank.

Have the GPX? Send us the link.

We want the address of the file the race publishes, not the file. We download it from there so the page can say where the line came from.

The page or file on the race's own site.

Optional, and only so we can ask you a question about it.

Are you the race director? Get in touch and we'll make it right.

We read every one of these and we write back. Every fact here carries the source it came from, and the way a wrong one gets fixed is a person checking it against what you tell us.

Required, because this is a conversation and we write back.

Tell us what is wrong, out of date, or missing on this page. We read every one of these and we will get back to you.

Optional.

So we know who we are writing back to.

Optional. Director, assistant, comms, whoever you are.

Leave this field blank.

Where this came from. Every fact on this page records its source and when we last checked it: 116 sources for this race. Hover a source link to read the sentence it came from.
48% of what we track for a course is filled in. The rest says "not checked yet" rather than guessing.
See something wrong or out of date? Suggest an edit
Ran this race? Tell the next runner what you know
Were you out there? Say which stops a text got out from
Got footage of this course? Send us the link
Are you the race director? Get in touch and we'll make it right.
Anything else: [email protected]

Ultras change. We will tell you when this one does.

Cutoffs move, races get postponed, lotteries open and close. We read the race's own sources and record where every fact came from. Put your email in and we will send you what changed, and where we read it.

No account, and nothing to cancel.

What happens to your email. Nothing else. I do not sell it, and I will not send you anything except this race changing. One click gets you out.

I keep this catalog because the information is scattered and hard to trust. Telling you when it moves is the same job.

Ultras change. We will tell you when this one does.

Cutoffs move, races get postponed, lotteries open and close. We read the race's own sources and record where every fact came from. Put your email in and we will send you what changed, and where we read it.

No account, and nothing to cancel.

What happens to your email. Nothing else. I do not sell it, and I will not send you anything except this race changing. One click gets you out.

I keep this catalog because the information is scattered and hard to trust. Telling you when it moves is the same job.