Loading Race For You
Loading page content.
entries openAction Challenge Ltd
North Downs 50 Challenge
Ultra Challenge
Next edition: Saturday, 31 July 2027Loseley Park Guildford, England
North Downs 50 Challenge is a looped trail ultramarathon based at Loseley Park Guildford.
Official race site (opens in a new tab)
Optional device-only history; never synced to your account. Shared-device users can leave it off.
Distance31.1 mi
Ascent830m*
Climb / km16.6m
CutoffNo fixed limit
Cutoff paceNot applicable
TechnicalityUnknown
Entry£139
FormatLooped
Next edition
31 July 2027
This is the most relevant confirmed edition currently held for the permanent race family. Edition-specific facts should still be checked against the final organiser instructions.
Edition archive
This is the only edition currently stored for this race family. Earlier verified editions can be added without changing the permanent race URL.
Check the official race source (opens in a new tab)Race For You difficulty
3.2/ 10
Beginner-friendly
Moderate evidence confidence · 62% evidence coverage
This score is driven most by balanced overall demands. Difficulty V2's separate time-limit modifier adds 0.00 points here and is capped at 0.70; a broad limit cannot erase extreme intrinsic demand. This is independent of the public Cutoff Pressure V2 band.
Weather, conditions and individual preparation can change the real difficulty significantly.
How the score works Distance, weighted 30 percent3 out of 10
Climbing, weighted 25 percent2.7 out of 10
Technicality, weighted 15 percent5.5 out of 10
Accumulated burden, weighted 17 percent1.9 out of 10
Exposure & support, weighted 13 percent3.9 out of 10
Course analysis
What shapes this race
The course combines trail, mixed terrain.
trailmixed
Climbing density
16.6m per km
A more useful comparison than total ascent alone: it shows how consistently the course asks you to climb.
Cutoff analysis
No fixed limit
The organiser explicitly publishes no fixed overall time limit. Continue to follow every event rule, checkpoint instruction and safety requirement.
Who this suits
First ultra?
There is not enough verified information to assess first-ultra suitability yet.
Navigation
fully marked
The route is described as marked, but runners should still read the final race instructions.
Exposure & kit
unknown kit
Night-running exposure has not been verified for this edition. Check the organiser’s latest schedule, route information and final kit rules.
Personal race predictor
Will you make the cutoff?
Use a previous result to estimate a realistic range for North Downs 50 Challenge, your potential buffer and the biggest change in demand.
Practical detail
Support & logistics
StartLoseley Park Guildford
FinishLoseley Park Guildford
Support levelfully supported
Logistics are only shown where currently recorded. Confirm parking, transport, crew access and final aid-station plans with the organiser.
Latest verification
Trust the source, see the gaps.
Data PartialThe cited 2027 edition sources were reviewed on 4 September 2026 and support the recorded date, distance, ascent, cutoff state, format and lifecycle. Unresolved facts remain marked unknown rather than being inferred.
- Successful source check
- 4 Sept 2026
- Catalogue record updated
- 4 Sept 2026
- Official source
- Available
Elevation is approximate or awaiting final confirmation.
Event details can change after a successful source check. Confirm the final route, kit, cutoff, price and entry terms directly with the organiser before entering or travelling.
Found something wrong?
Help keep this race accurate.
Wrong cutoff? Date changed? New course? Tell us what moved and include the official source if you have it.
Report an updateKeep exploring
Browse the race catalogue
Use explicit distance, place, date, terrain and format filters to compare current races.