Nathrop, CO, United States · Sunday, September 27, 2026

Fixed Distance 50K

Sawatch Ascent 50km Race

Race completed

50 km Distance

3,300 m Climbing

7.5 Grit · Hardcore

38.7459° N, 106.0785° W © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 66 m / km Mountain. Significant climbing. Steep sections will require power hiking.

Time limit 11 hours 13:12 min/km average. Generous. Walkable throughout for most of the field. More forgiving than 62% of 50K races. Measured against 1034 races of the same distance. Cut-off calculator →

Field size ~166 Mid-sized. Company early, well spread out by halfway.

DUV results for the 2025 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Typical conditions, September

Daytime high 18°C

Night low 3°C

Rainfall Mostly dry

Daylight 12 h 00 m of light

Regional 2001-2020 average for September — NASA POWER, grid elevation 2991 m. Not a forecast.

Results history

Year	Race	Finishers	Men's winner	Women's winner
2025	50km	166	Justin Grunewald · 04:41:18	Addie Bracy · 05:35:08
2024	50km	176	Kieran Nay · 04:58:42	Lindsey Anderson · 06:07:05
2023	50km	120	Jeason Murphy · 05:45:39	Lauren Puretz · 05:42:42

The field shrank 6% between 2024 (176) and 2025 (166). 40% of the 2025 field were women.

DUV results for the 2025 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

The Aid Station

Course-specific beta from the community

⛰️ terrain

This is a mountain course. Poles are highly recommended for the sustained climbs.

By UltraHub Expert

👟 gear

With trail terrain, choose a shoe with moderate cushioning for optimal performance.

By UltraHub Expert

Gear for this race

Chosen for 50 km of trail with 3,300 m of ascent.

Trail Running Shoes 66 m of climb per kilometre — grip and rock protection before cushioning.
Race Nutrition 50 km of self-supported fuelling between aid stations.
Hydration Vests Pole attachment and chest-strap stability on steep ground.
Trekking Poles 3,300 m of ascent to walk up.
GPS Watches Battery life first — a 50 km day outlasts most full-GPS modes.

La Sportiva

Prodigio Pro

RunRepeat found the La Sportiva Prodigio Pro to have a secure, locked-in fit due to its premium upper, and also praised the shoe's energetic ride, particularly…

$225 ★★★★★ 4.6

Salomon

Sense Ride 5

RunRepeat found the Salomon Sense Ride 5 to have immaculate lockdown and a smooth and stable ride, making it confident on moderate trails and steep downhills. I…

★★★★★ 4.5

Spring Energy

Awesome Sauce

Real food gel with 180 calories. Rice-based with natural flavors.

$4 ★★★★★ 4.6

Salomon

ADV Skin 12

Industry-standard 12L race vest with front flask pockets and minimal bounce.

$180 ★★★★★ 4.8

Komperdell

Carbon Ultralight Vario 4

4-section folding carbon poles with compact pack size for mandatory gear.

$160 ★★★★★ 4.5

Suunto

Vertical

Titanium GPS watch with solar charging, offline maps, and 140-hour GPS battery.

$630 ★★★★★ 4.5

All gear guides →

Overview

The Sawatch Ascent 50km Race, organised by West Line Winder, offers a significant challenge with 3300m of elevation gain over its 50km course in Nathrop, CO. This amounts to 66m of climb per kilometer, making it a demanding trail race. Runners will reach elevations of 13150 feet.

With 166 finishers in its latest edition, this race has a larger field than 88% of its 2663 peer 50k events. The 11-hour time limit gives a cutoff pace of 13.2 minutes per kilometer, which is more generous than 34% of 1022 peer 50k races, allowing more time to complete the course.

The race, first held in 2023, will next take place on September 27, 2026.

Similar races

Other 50K trail ultras, closest in distance first.