Ultra-Trail Snowdonia - Eryri 100M 2027
The forecast arrives five days before the start.
Here you'll find the elevation profile, an estimated finish time based on your UTMB Index and details of the 13 aid stations to plan your nutrition and hydration segment by segment.
What's your time based on your UTMB?
Times estimated by the RAVIT model, learned from real ultra-trail finish times. Enter your UTMB Index (utmb.world) to get a personalized estimate.
Cut-off times and crew - Ultra-Trail Snowdonia - Eryri 100M · 2027
Data from the official race rules, checked for every edition. The race rules prevail. Positions are interpolated along the GPX track and are a guide, not official course marking.
What you'll find at each aid station
| Product | Pen-y-Passkm 12.0 | Ogwen Valleykm 21.9 | Llyn Eigiaukm 37.2 | Capel Curigkm 49.5 | Dolwyddelankm 59.8 | Blaenau Ffestiniogkm 72.3 | Croesorkm 84.6 | Gwastadanas Farmkm 98.2 | Beddgelertkm 112.3 | Rhyd-Ddukm 126.7 | Bron-y-Fedw Uchafkm 139.2 | Betws Garmonkm 147.5 | Llanberiskm 163.9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ | ✕ |
| Brand products · Näak | unavailable | ✕ | ✕ | unavailable | ✕ | ✕ | unavailable | ✕ | unavailable | ✕ | ✕ | ✕ | unavailable |
| Hot meal | unavailable | unavailable | unavailable | ✕ | unavailable | unavailable | ✕ | unavailable | ✕ | unavailable | unavailable | unavailable | ✕ |
Elevation profile
The course and its aid stations
Ultra-Trail Snowdonia - Eryri 100M: times, aid-station stops and fuelling needs by UTMB® Index
Between a UTMB® Index of 500 and 800, the estimated finish time on this race runs from 38h45 to 24h09, and the aid-station stop budget from 6h13 to 1h16. The longer the race, the more stops weigh: this is time you should plan to spend standing still, not only running.
Below a UTMB® Index of roughly 350, the overall cut-off of 48h00 is no longer reachable at the estimated pace.
| UTMB® Index | Estimated time | Of which stops | Night hours | Carbs | Fluid | Sodium | Cut-off margin |
|---|---|---|---|---|---|---|---|
| 500 | 38h45 | 6h13 | 17.8 | 2,325 g | 27.1 L | 19,373 mg | +9h15 |
| 550 | 36h31 | 5h15 | 15.5 | 2,191 g | 25.6 L | 18,256 mg | +11h29 |
| 600 | 33h56 | 4h14 | 12.9 | 2,036 g | 23.8 L | 16,966 mg | +14h04 |
| 650 | 30h31 | 2h59 | 10 | 1,831 g | 21.4 L | 15,256 mg | +17h29 |
| 700 | 28h24 | 2h14 | 10 | 1,704 g | 19.9 L | 14,202 mg | +19h36 |
| 750 | 26h22 | 1h41 | 10 | 1,582 g | 18.5 L | 13,181 mg | +21h38 |
| 800 | 24h09 | 1h16 | 10 | 1,449 g | 16.9 L | 12,074 mg | +23h51 |
Figures based on 60 g of carbohydrate, 700 mL of fluid and 500 mg of sodium per hour, "average" preparation and mild conditions (15–25 °C). Above 25 °C, count on roughly 900 mL/h and 700 mg/h. Carbohydrate intake is trained: 60 g/h is a floor, 90 g/h assumes a glucose-fructose blend and a gut used to it.
Other trails worth preparing for
- Centurion A100158 km · 1,087 m D+ · October 17, 2026
- North Coast 110170 km · 4,705 m D+ · November 7, 2026
- Spine Challenger North242 km · 6,465 m D+ · January 10, 2027
- Arc of Attrition - Arc 100M173 km · 5,318 m D+ · January 22, 2027
- Eryri by UTMB® - Eryri 100M®164 km · 9,356 m D+ · May 14, 2027
- Ultra-Trail Snowdonia - Eryri 100K107 km · 5,518 m D+ · May 15, 2027
- Eryri by UTMB® - Eryri 100K®107 km · 5,518 m D+ · May 15, 2027
- UK Ultra South Downs 100 Mile162 km · 3,466 m D+ · October 3, 2026
- 7 Valleys Ultra109 km · 3,906 m D+ · September 26, 2026
Sources and method
- Time projection — les temps par cote sont repris des passages réels des coureurs de chaque tranche sur les éditions précédentes de cette course, arrêts aux ravitaillements compris. Aucune formule n'intervient tant que ces résultats existent.
- Trail nutrition — hourly targets for carbohydrate, fluid and sodium follow the commonly accepted ultra-endurance guidance. La Clinique du Coureur — Fuelling in trail running
- Course, aid stations and cut-offs — taken from the event's official rules, which prevail in case of any discrepancy. Official site — Ultra-Trail Snowdonia - Eryri 100M
Weather for Ultra-Trail Snowdonia - Eryri 100M
The weather for Ultra-Trail Snowdonia - Eryri 100M will appear here as soon as the forecast models reach that date, around five days before the start: feels-like temperature, rain, snow, wind and storms, section by section and at your passage time.
Detailed weather for Ultra-Trail Snowdonia - Eryri 100M, hour by hour on the courseFrequently asked questions
How many checkpoints?
Ultra-Trail Snowdonia - Eryri 100M has 13 checkpoints: 12 aid stations and 1 water point. Details are in the two tables above.
What's the longest segment without aid?
The one leading to Llanberis: 16.4 km and 777 m elevation gain. That's the one to load up for first.
How do I find the exact location of an aid station?
The Google Maps icon in the “Access” column opens the aid station's location: handy for planning your crew's routes.
What distance and elevation gain?
Ultra-Trail Snowdonia - Eryri 100M is 164 km long with 9356 m of elevation gain.
How long to finish?
With a UTMB Index of 600 (average runner), the estimated time is around 33h56 for Ultra-Trail Snowdonia - Eryri 100M.
What's the weather forecast?
The weather for Ultra-Trail Snowdonia - Eryri 100M will be published on this page around five days before the start, once the forecast models reach the race date. It will be detailed section by section: feels-like temperature, rain, snow, wind and storms.
Want to stack the odds in your favor for Ultra-Trail Snowdonia - Eryri 100M?
In 2 minutes, RAVIT generates your complete plan: segment-by-segment time, carbs, water and sodium at every aid station, printable roadbook.
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