Races
Istria
Labin to Umag across the Istrian peninsula. Six thousand eight hundred meters. Učka, Buzet, Motovun. Coasteering, forests, and medieval stone.
168 km+16,208 ft-17,166 ft46 hours20 ft to 4,362 fttech 5/106 stations4 Running StonesMotovunUčkaWSER qualifierAprilRunning Stones · 4 stones
Distance168 km
Gain+16,208 ft
Loss-17,166 ft
Altitude20 ft to 4,362 ft
Technicality5/10
Air45°F to 75°F
- Start978 ft
- High4,362 ft
- Low20 ft
- Finish20 ft
- Labin at mile 0.0
- Labin to Umag at mile 21, cutoff 9.200000000000001 hours
- Croatia at mile 42, cutoff 18.400000000000002 hours
- Istria mile 63 at mile 63, cutoff 27.599999999999998 hours
- Istria mile 84 at mile 83, cutoff 36.800000000000004 hours
- Finish Umag across the Istrian peninsula at mile 104, cutoff 46 hours
Field, 2026 · 13-year sampleresults
Starters374
Finish rate68%
Median32:56
Sub-2422
Geometrycourse math
Steepest drop1,490 ft-12.8% over 2.2 mi
Night miles42 misunset near 18:00 local
Course records
Men17:40:34Jim WALMSLEY
Women20:14:52Ragna DEBATS
The cruxUčka mountain climb and mainland Motovun section after Buzet (near mile 68)
Course DNA
The Course
Istria runs 168 km through Labin to Umag, Croatia. +16,208 ft gain and -17,166 ft loss. Surfaces skew 65% trail / 25% dirt road / 10% coastal rocky. Učka mountain climb and mainland Motovun section after Buzet. High point near 4,362 ft. Low near 20 ft. April temps run 45°F to 75°F. The course rewards patience early and punishes rushed descents after mile 52.
The Work
Train for 16,208 feet of climbing across 168 km. Back-to-back long runs on trail. Practice power-hiking grades above 15 percent. 46 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 68.
Kit
April in Labin to Umag, Croatia: plan for 45°F to 75°F. Mandatory shell if rain is in forecast. Headlamp with spare batteries if 46 hours pushes past dark. Poles help on sustained climbs above mile 26. Vest capacity for 2 liters minimum. Shoes matched to 65% trail: lugs for mud, rock plate if the course turns technical after mile 52.
Race Day
Hold effort through mile 26. The field often splits on the first big climb after mile 52. Učka mountain climb and mainland Motovun section after Buzet near mile 68 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.
Results
Istria finish lines.
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Sources (4)
- Field stats (2026): https://utmb.world/utmb-index/races/1572.istria100byutmb-r-168k.2026?page=1
- Qualifier: utmb_stones: https://utmb.world/utmb-world-series
- Course record (M): https://utmb.world/utmb-index/races/1572.istria100byutmb-r-168k.2023?page=1
- Course record (F): https://utmb.world/utmb-index/races/1572.istria100byutmb-r-168k.2022?page=1