Races
Ultra Trail Snowdonia
One hundred sixty-five kilometers through Snowdonia. Two days of Welsh bog, rock, and ridge.
- Start351 ft
- High551 ft
- Low351 ft
- Finish476 ft
Geometryderived
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. +4,191 ft gain and -4,066 ft loss. Surfaces skew 70% trail / 25% bog / 5% road. Second day Welsh ridge miles in bog and rain with full sleep debt. High point near 551 ft. Low near 351 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 4,191 feet of 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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