North Chilterns 50km

33 days away

50 km Distance

800 m Climbing

3.7 Grit · Challenging

51.9103° N, 0.3740° W © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 16 m / km Rolling. Moderate undulations. Requires consistent effort across varying grades.

Time limit 9 hours 10:48 min/km average. Firm. Room to walk the climbs and stop at aid. About average for a 50K. Measured against 1063 races of the same distance. Cut-off calculator →

Field size ~133 Mid-sized. Company early, well spread out by halfway.

DUV results for the 2025 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Typical conditions, November

Daylight 8 h 35 m of light

Results history

Year	Race	Finishers	Men's winner	Women's winner
2025	50km	133	Edouard Picard · 03:44:26	Zoe Smith · 04:13:45
2024	50km	169	Mike van der Merwe · 03:36:45	Ruth dos Remedios · 04:48:52
2023	50km	129	Damian Carr · 03:54:50	Michelle Margaret Joy Attridge · 04:30:13
2022	50km	92	Alex Cawthorne · 04:05:20	Jessica Johnson · 04:38:35

The field shrank 21% between 2024 (169) and 2025 (133). 25% of the 2025 field were women.

DUV results for the 2025 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Course notes

terrain This is a rolling course. Expect fast, runnable sections where rhythm is key.
gear With trail terrain, choose a shoe with moderate cushioning for optimal performance.

Gear for this race

Chosen for 50 km of trail with 800 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.

Adidas

Terrex Speed Ultra

RunRepeat found the Adidas Terrex Speed Ultra to have a grippy outsole and great lockdown, while iRunFar noted that the shoe works on a variety of trail conditi…

★★★★★ 4.5

La Sportiva

Prodigio Pro

RunRepeat found the La Sportiva Prodigio Pro to have a secure, locked-in fit due to its premium upper, and also praised the shoe's energetic ride, particularly…

$225 ★★★★★ 4.6

Tailwind

Endurance Fuel

All-in-one calorie and electrolyte drink mix. 200 calories per serving.

$25 ★★★★★ 4.8

Nathan

VaporKrar 12L

12L race vest co-designed with ultra champion Rob Krar, with insulated bladder pocket.

$170 ★★★★★ 4.6

COROS

APEX 2 Pro

GPS running watch with 75-hour GPS battery, topo maps, and training metrics.

$500 ★★★★★ 4.7

All gear guides →

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