Istria 100 by UTMB® 21K is a 21.5 km trail race of Istria 100 by UTMB 2027 in Grožnjan, Croatia. The race starts on April 4, 2027 at 10:00 AM. It starts in Grožnjan and finishes in Umag. The time limit is 4 h.
The course climbs 157 m+. With 7 m/km of climbing, the course is predominantly runnable. By gradient, 4% of the distance is uphill, 14% downhill and 82% flat. The longest climb runs 0.8 km at an average 5.7% grade (47 m of vertical). The longest descent runs 1.0 km at 6.8% (67 m of vertical). The steepest climb averages 8.8% over 0.5 km. The steepest descent drops at 12.1% over 0.3 km. Surface: 53% smooth, 23% trail, and 21% road. Flat-equivalent effort: 21.3 FlatKM.
The course is runnable enough that trekking poles are not needed.
This page has the interactive elevation profile, gradient matrix, pacing and nutrition planner and weather climatology for Istria 100 by UTMB® 21K.
Other distances of Istria 100 by UTMB 2027Istria 100 by UTMB® 168K (168 km)·Istria 100 by UTMB® 110K (111 km)·Istria 100 by UTMB® 69K (69.6 km)·Istria 100 by UTMB® 42K (42.0 km)
Other editions of Istria 100 by UTMB® 21K2026·2025
Official websiteistria.utmb.world
