Races
Ultra Trail Snowdonia
One hundred sixty-five kilometers through Snowdonia. Two days of Welsh bog, rock, and ridge.
- Start30 ft
- High1,685 ft
- Low30 ft
- Finish797 ft
- Caernarfon at mile 0.0
- Ultra Trail Snowdonia mile 20 at mile 20, cutoff 9.600000000000001 hours
- Ultra Trail Snowdonia mile 39 at mile 39, cutoff 19.200000000000003 hours
- Ultra Trail Snowdonia mile 59 at mile 59, cutoff 28.799999999999997 hours
- Ultra Trail Snowdonia mile 78 at mile 78, cutoff 38.400000000000006 hours
- Finish Wales at mile 98, cutoff 48 hours
Geometrycourse math
The cruxSecond day Welsh ridge miles in bog and rain with full sleep debt (near mile 67)
Course DNA
The Course
Ultra Trail Snowdonia runs 165 km through Caernarfon, Wales. Surfaces skew 70% trail / 25% bog / 5% road. Second day Welsh ridge miles in bog and rain with full sleep debt. High point near 1,713 ft. Low near 16 ft. May temps run 35°F to 65°F. The course rewards patience early and punishes rushed descents after mile 51.
The Work
Train for the climbing across 165 km. Back-to-back long runs on trail. Practice power-hiking grades above 15 percent. 48 hours total means limited margin: rehearse fueling every 45 to 60 minutes and downhill eccentric work weekly. Technicality 5/10. Build a block that simulates the crux near mile 67.
Kit
May in Caernarfon, Wales: plan for 35°F to 65°F. Mandatory shell if rain is in forecast. Headlamp with spare batteries if 48 hours pushes past dark. Poles help on sustained climbs above mile 26. Vest capacity for 2 liters minimum. Shoes matched to 70% trail: lugs for mud, rock plate if the course turns technical after mile 51.
Race Day
Hold effort through mile 26. The field often splits on the first big climb after mile 51. Second day Welsh ridge miles in bog and rain with full sleep debt near mile 67 is where time is won or lost. Walk the steep pinches. Run the flats and gentle downhills. Crew at major aids: socks, calories, ice if hot. Transitions under 5 minutes when possible. Final third is 34 miles of fatigue management. Finish with reserve for the last descent.
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