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Eiger Ultra Trail by UTMB
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Trail Surprise

UTMB World Series
15.0km·800m+
July 15
Grindelwald,
Switzerland
utmb·source

Race Pace Calculator · GPX Analyzer · Trail Finder

Other races: Switzerland

Read

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  • Hill Training for Trail Runners: Train the Descents
  • Downhill Running Muscle Damage: Why Descents Wreck Quads

Full calendar: Switzerland

Trail Surprise · Race profile

Distance
15.0km
Gain
800m+
FlatKM
20.0
Max
1646m
Min
1036m

About Trail Surprise

Trail Surprise is the 15.0km trail race at Eiger Ultra Trail by UTMB 2025 (Grindelwald, Switzerland). The race starts on July 15, 2025.

Race strategy

Run the climb at race pace, build your speed on the downhill, and go all out at the finish.

  • Final 628m descent. Save your legs to go all out on it.
  • Steep 25% wall. Control your pace and stay focused.
  • Control your HR on the first mountain, and go all out on the final descent from 11.0km.
  • Start · 0.0km–2.3km · Race-day nerves push your heart rate up: don't follow the crowd, find your own rhythm.
  • Settle in · 2.3km–11.0km · Climb of 758m, high point 1646m. Ease in: hold back more than feels necessary. The race is still ahead. Climb by heart rate or breathing, not pace.
  • Home · 11.0km–16.5km · Descent of 628m averaging 11%. Build to the finish: leave whatever you have left out on the course. Long descent: keep it even and let go only near the end. Hike the steepest pitches.

Course

The course climbs 800m+. With 53m/km of climbing, this is a true mountain course with sustained climbs and descents. By gradient, 49% of the distance is uphill, 32% downhill and 19% flat. The longest climb runs 11.0km at an average 6.9% grade (758m of vertical). The longest descent runs 5.5km at an average 11.4% grade (628m of vertical). The steepest climb averages 15.9% over 0.4km. The steepest descent drops at 25.9% over 0.3km. Surface: 56% trail, 31% road, and 13% smooth. Flat-equivalent effort: 20.0 FlatKM.

Poles

The course is runnable enough that trekking poles are not needed.

Quad damage

Quad damage risk is low (index 12 of 100): a few descents worth noting, none of them decisive.

  • Control your HR on the first mountain, and go all out on the final descent from 11.0km.
  • 11.0–16.5 km · 628 m D−, -11.4% · 0.0 km ahead → even, let go at the end

Weather

On race day, start temperatures have historically ranged from 12°C to 22°C, with around 16°C at the highest point; the chance of precipitation is about 60%.

Results

206 finishers completed the 2025 edition. Men's winner: Raoul Raus (Belgium) in 1:12:19. Women's winner: Deborah Chiarello (Switzerland) in 1:19:23.

This page has the full results and splits, a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Trail Surprise.

Other distances of Eiger Ultra Trail by UTMB 2025E250 - UNESCO Trail (250km)·E101 Ultra Trail (69.0km)·E51 Panorama Trail (41.0km)·E35 - North Face Trail (33.0km)·E16 - Pleasure Trail (16.0km)

Official websiteeiger.utmb.world