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The Rut Mountain Runs
50km5028km2821km2111km114.6km4.6

The Rut Mountain Runs 21k

21.0km·1220m+
September 11, 10:00 AM
Big Sky Resort base area,
United States
itra·utmb·source

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The Rut Mountain Runs 21k · Race profile

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Read

  • How to Taper for a Marathon, Half Marathon or Ultra
  • Types of Runs and What Each Workout Actually Trains
  • Hill Training for Trail Runners: Train the Descents
Distance
21.0km
Gain
1220m+
FlatKM
31.8
Max
2967m
Min
2212m

Full calendar: United States

About The Rut Mountain Runs 21k

The Rut Mountain Runs 21k is the 21.0km trail race at The Rut Mountain Runs 2026 (Big Sky Resort base area, United States). The race starts on September 11, 2026 at 10:00 AM. It starts and finishes in Big Sky Resort base area. The time limit is 7 h.

Race strategy

Hold a steady pace and save energy for every section.

  • High point at 2967m. Control your HR at altitude.
  • 651m descent. Go easy, save your quads.
  • Control your HR on the first mountain, save your quads on the descents until 12.6km, then run your race pace.
  • Start · 0.0km–1.4km · Race-day nerves push your heart rate up: don't follow the crowd, find your own rhythm.
  • Settle in · 1.4km–5.5km · Climb of 650m. Ease in: hold back more than feels necessary. The race is still ahead. Climb by heart rate or breathing, not pace. At altitude your pace drops, and that's fine.
  • Work · 5.5km–18.3km · Climb of 150m, high point 2967m, descent of 651m averaging 12%. Plus 1 more climb and 2 descents. 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. At altitude your pace drops, and that's fine.
  • Home · 18.3km–20.5km · Climb of 115m. Build to the finish: leave whatever you have left out on the course. Climb by heart rate or breathing, not pace.

Course

The course climbs 1220m+. With 58m/km of climbing, this is a true mountain course with sustained climbs and descents. By gradient, 44% of the distance is uphill, 47% downhill and 9% flat. The longest climb runs 5.5km at an average 11.8% grade (650m of vertical). The longest descent runs 5.5km at an average 11.9% grade (651m of vertical). The steepest climb averages 21.6% over 0.5km. The steepest descent drops at 23.8% over 0.6km. Flat-equivalent effort: 31.8 FlatKM.

Summits

The course also passes close to Andesite Mountain (2661m).

Poles

Trekking poles are worth taking: about 3.6km of the course favours them.

Quad damage

Quad damage risk is moderate (index 20 of 100), with 63% of the load in the first half: 1 descent deserves a plan and a couple of downhill sessions before race day.

  • Control your HR on the first mountain, save your quads on the descents until 12.6km, then run your race pace.
  • #1 · 7.2–12.6 km · 651 m D−, -11.9% · 7.9 km ahead → control
  • 14.7–18.3 km · 435 m D−, -12.1% · 2.2 km ahead → your pace

Weather

On race day, start temperatures have historically ranged from 6°C to 18°C, with around 12°C at the highest point; the chance of precipitation is about 30%. Heavy rain of 10.0mm or more falls on about 3% of days around this date.

Results

682 finishers completed the 2026 edition. Men's winner: Gavin Galyardt (United States) in 2:11:27. Women's winner: Ava Ashby (United States) in 2:26:35.

This page has the full results and splits, a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for The Rut Mountain Runs 21k.

Other distances of The Rut Mountain Runs 2026The Rut Mountain Runs 50k (50.0km)·The Rut Mountain Runs 28k (28.0km)·The Rut Mountain Runs 11k (11.0km)·The Rut Mountain Runs Lone Peak Vertical Kilometer (4.6km)

Other editions of The Rut Mountain Runs 21k2027·2025

Official websiteruntherut.com