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Istria 100 by UTMB
168km168111km11169.6km69.642km4221.5km21.5

Istria 100 by UTMB® 69K

UTMB World Series
69.6km·2400m+
April 3, 09:00 AM
Buzet,
Croatia
utmb·source

Race Pace Calculator · GPX Analyzer · Trail Finder

Other races: Croatia

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Full calendar: Croatia

Istria 100 by UTMB® 69K · Race profile

Distance
69.6km
Gain
2400m+
FlatKM
83.5
Max
400m
Min
0m

About Istria 100 by UTMB® 69K

Istria 100 by UTMB® 69K is the 69.6km ultra trail at Istria 100 by UTMB 2027 (Buzet, Croatia). The race starts on April 3, 2027 at 09:00 AM. It starts in Buzet and finishes in Umag. The time limit is 15 h.

Race strategy

Hold a steady pace and save energy for every section.

  • 326m descent. Go easy, save your quads.
  • The finish is runnable. Save your legs to run it all the way.
  • Control your HR on the first climb, save your quads on the descents until 24.0km, then run your race pace.
  • Start · 0.0km–1.9km · Race-day nerves push your heart rate up: don't follow the crowd, find your own rhythm.
  • Settle in · 1.9km–14.3km · Descent of 326m averaging 11%. Plus 2 more climbs. Ease in: hold back more than feels necessary. The race is still ahead. Climb by heart rate or breathing, not pace. This descent is hard on the legs: short steps, stay in control, poles if you have them. Running pays off here: run wherever you can.
  • Work · 14.3km–29.6km · Climb of 461m, high point 400m, descent of 378m averaging 13%. Plus 1 more climb and 1 descent. This is where the race is built: steady, solid effort. Climb by heart rate or breathing, not pace. This descent is hard on the legs: short steps, stay in control, poles if you have them.
  • Fade · 29.6km–43.7km · Climb of 619m. Your energy fades, and that's normal: hold a steady effort and stop counting the miles. Climb by heart rate or breathing, not pace. Your heart rate drifts down on its own: don't chase your early-race numbers, go by feel.
  • Home · 43.7km–68.8km · 25.2km of runnable trail. No heroics: settle back into your own effort and hold it to the line. Running pays off here: run wherever you can.

Course

The course climbs 2400m+. With 34m/km of climbing, this is a rolling, mostly runnable course. By gradient, 26% of the distance is uphill, 32% downhill and 42% flat. The longest climb runs 14.1km at an average 4.4% grade (619m of vertical). The longest descent runs 3.0km at an average 10.9% grade (326m of vertical). The steepest climb averages 21.9% over 1.0km. The steepest descent drops at 27.0% over 0.2km. Surface: 40% smooth, 32% trail, and 22% road. Flat-equivalent effort: 83.5 FlatKM.

Summits

The course also passes close to Sv. Jure (384m), Pelegrin (185m), and Starola (165m).

Poles

Poles bring little benefit here: only about 10.1km of pole-friendly terrain.

Quad damage

Quad damage risk is moderate (index 29 of 100), with 71% of the load in the first half: 2 descents deserve a plan and a couple of downhill sessions before race day.

  • Control your HR on the first climb, save your quads on the descents until 24.0km, then run your race pace.
  • #1 · 11.3–14.3 km · 326 m D−, -10.9% · 54.5 km ahead → control
  • #2 · 21.2–24.0 km · 378 m D−, -13.5% · 44.9 km ahead → control

This page has a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Istria 100 by UTMB® 69K.

Other distances of Istria 100 by UTMB 2027Istria 100 by UTMB® 168K (168km)·Istria 100 by UTMB® 110K (111km)·Istria 100 by UTMB® 42K (42.0km)·Istria 100 by UTMB® 21K (21.5km)

Other editions of Istria 100 by UTMB® 69K2026·2025

Official websiteistria.utmb.world