Istria 100 by UTMB® 21K is the 21.0km trail race at Istria 100 by UTMB 2025 (Umag, Croatia). The race starts on April 13, 2025 at 10:00 AM.
The course climbs 150m+. With 7m/km of climbing, the course is predominantly runnable. By gradient, 4% of the distance is uphill, 14% downhill and 82% flat. Surface: 53% smooth, 23% trail, and 21% road. Flat-equivalent effort: 20.8 FlatKM.
The course also passes close to Pelegrin (185m) and Starola (165m).
The course is runnable enough that trekking poles are not needed.
There is too little runnable descent to damage the quads: plan the race around climbing and fuelling.
349 finishers completed the 2025 edition. Men's winner: Johannes Nussbaumer (Austria) in 1:11:42. Women's winner: Caterina Stenta (Italy) in 1:29:18.
This page has the full results and splits, a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Istria 100 by UTMB® 21K.
Other distances of Istria 100 by UTMB 2025Istria 100 by UTMB® 168K (168km)·Istria 100 by UTMB® 110K (110km)·Istria 100 by UTMB® 69K (69.0km)·Istria 100 by UTMB® 42K (42.0km)
Other editions of Istria 100 by UTMB® 21K2027·2026
Official websiteistria.utmb.world
