How far is the Arc 20K?

The Arc 20K is one distance: 20K (12.4 miles).

How hard is the Arc 20K?

20K: Hard. TRP grades come from distance and climb measured off the course file, not from the organiser.

Is the Arc 20K course marked?

No. The Arc 20K is not a marked course. You are expected to navigate it yourself.

What are the cut-offs for the Arc 20K?

Overall time limits — 20K: 4h.

Can I download the Arc 20K route?

Yes. The GPX for each distance is free to download here, with no sign-up, the same as every route on Trail Running Planet.

When is the next Arc 20K?

Sun, 24 Jan 2027, 11:00. Entries open.

Arc of Attrition by UTMB Arc 20K

Perranporth Airfield, CornwallSun, 24 Jan 2027

Twenty kilometres out of Perranporth Airfield to finish the weekend.

20K

12 miles

700 m ascent

35 m per km

4h cut-off

12:00/km to make it

coastalcliffNavigation required

Nobody has reviewed this one yet

No reviews of the Arc 20K, and nothing on what people wore. Both are things no organiser publishes and every runner wants before they enter — how it actually went, and what was on your feet.

Ran it? Write the first review

Running it soon? Connect Strava and we will ask you about it the day you finish, so you do not have to remember to come back.

The course

Loading map…

HARD

TRP grade · E3·T3

4h cut-off, which needs 12:00/km

2 checkpoints

Download GPXFree, no sign-up.

This file is from a previous running and the course may have changed since. If you are navigating with it, get the current version from Arc of Attrition by UTMB first.

Partner · affiliate policy

How to enter

Sun, 24 Jan 2027 · Entries open

Enter via UTMB World Series ↗

Entries are handled by UTMB World Series, not by us. We take nothing for sending you there.

Add to your calendar · with the start time

Common questions

: The Arc 20K is one distance: 20K (12.4 miles).
: The 20K has 700 m of ascent.
: 20K: Hard. TRP grades come from distance and climb measured off the course file, not from the organiser.
: No. The Arc 20K is not a marked course. You are expected to navigate it yourself.
: We don't hold a compulsory kit list for the Arc 20K. Arc of Attrition by UTMB confirm mandatory kit in their race information, usually in the final instructions.
: Overall time limits — 20K: 4h.
: We don't hold a checkpoint list for the Arc 20K. What's on the table varies a lot between races, so check the Arc of Attrition by UTMB race information rather than turning up expecting food.
: Yes. The GPX for each distance is free to download here, with no sign-up, the same as every route on Trail Running Planet.
: Sun, 24 Jan 2027, 11:00. Entries open.