Races
Ultra Trail Snowdonia
Snowdonia. Welsh ridgelines. Bog, rock, and cloud. One hundred kilometers beneath the 3000s.
- Start30 ft
- High1,688 ft
- Low30 ft
- Finish459 ft
- Caernarfon at mile 0.0
- Ultra Trail Snowdonia mile 12 at mile 12, cutoff 5.6000000000000005 hours
- Ultra Trail Snowdonia mile 25 at mile 25, cutoff 11.200000000000001 hours
- Ultra Trail Snowdonia mile 37 at mile 37, cutoff 16.8 hours
- Ultra Trail Snowdonia mile 50 at mile 50, cutoff 22.400000000000002 hours
- Finish Wales at mile 62, cutoff 28 hours
Geometrycourse math
The cruxSnowdon Watkin Path approach in May rain and bog sections (near mile 40)
Course DNA
The Course
Ultra Trail Snowdonia runs 100 km through Caernarfon, Wales. +19,531 ft gain and -19,101 ft loss. Surfaces skew 70% trail / 25% bog / 5% road. Snowdon Watkin Path approach in May rain and bog sections. High point near 1,713 ft. Low near 26 ft. May temps run 40°F to 65°F. The course rewards patience early and punishes rushed descents after mile 31.
The Work
Train for 19,531 feet of climbing across 100 km. Back-to-back long runs on trail. Practice power-hiking grades above 15 percent. 28 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 40.
Kit
May in Caernarfon, Wales: plan for 40°F to 65°F. Mandatory shell if rain is in forecast. Headlamp with spare batteries if 28 hours pushes past dark. Poles help on sustained climbs above mile 16. Vest capacity for 2 liters minimum. Shoes matched to 70% trail: lugs for mud, rock plate if the course turns technical after mile 31.
Race Day
Hold effort through mile 16. The field often splits on the first big climb after mile 31. Snowdon Watkin Path approach in May rain and bog sections near mile 40 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 21 miles of fatigue management. Finish with reserve for the last descent.
Results
Ultra Trail Snowdonia finish lines.
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