Arc 20K is the 22.1km trail race at Arc of Attrition by UTMB 2027 (Perranporth, United Kingdom). The race starts on January 24, 2027 at 11:00 AM. The time limit is 4 h.
The course climbs 744m+. With 34m/km of climbing, this is a rolling, mostly runnable course. By gradient, 35% of the distance is uphill, 38% downhill and 27% flat. Surface: 48% trail, 31% smooth, and 18% road. Flat-equivalent effort: 26.5 FlatKM.
The highest summit on the course is St Agnes Beacon (192m), 15.4km from the start.
The course is runnable enough that trekking poles are not needed.
Quad damage risk is low (index 9 of 100): a few descents worth noting, none of them decisive.
On race day, start temperatures have historically ranged from 5°C to 11°C, with around 8°C at the highest point; the chance of precipitation is about 57%. Heavy rain of 10.0mm or more falls on about 13% of days around this date.
This page has a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Arc 20K.
Other distances of Arc of Attrition by UTMB 2027Arc 100M (173km)·Arc 100K (82.7km)·Arc 50K (49.4km)
Other editions of Arc 20K2026
Official websitearcofattrition.utmb.world
