Mansfield, United Kingdom · Sunday, July 12, 2026
Fixed Distance 50K
Rasselbock Ultra
Race completed
50 km Distance
510 m Climbing
3.3 Grit · Challenging
What the course asks
Climbing rate 10 m / km
Fast & Flat. This course is relatively flat and fast. Ideal for PB attempts.
Time limit 8 hours
9:36 min/km average. Comfortable. Room to walk the climbs and stop at aid. Tighter than 89% of 50K races. Measured against 984 races of the same distance. Cut-off calculator →
Typical conditions, July
Daytime high 21°C
Night low 12°C
Rainfall Mostly dry
Daylight 16 h 37 m of light
Regional 2001-2020 average for July — NASA POWER, grid elevation 112 m. Not a forecast.
The Aid Station
Course-specific beta from the community
This is a fast & flat course. Expect fast, runnable sections where rhythm is key.
With trail terrain, choose a shoe with moderate cushioning for optimal performance.
Gear for this race
Chosen for 50 km of trail with 510 m of ascent.
- Trail Running Shoes 50 km of trail — cushioning that is still there in the last quarter.
- Race Nutrition 50 km of self-supported fuelling between aid stations.
- Hydration Vests Flask capacity for 50 km, without the bounce.
- GPS Watches Battery life first — a 50 km day outlasts most full-GPS modes.
Course Notes
Two and a half loops around the stunning Sherwood Pines Forest in Nottinghamshire coming in at just over 50km.
Similar races
Other 50K trail ultras, closest in distance first.