Fort Collins, CO, United States · Saturday, October 31, 2026
Colorado 6 Hour Run
We hold no course length for this race — a timed or backyard event is measured by the clock, not the kilometre — so there is no Grit score to give you.
What the course asks
DUV results for the 2025 edition (6h) — ranked runners only. Starters are not published, so the field was at least this big and no finish rate can be given.
Typical conditions, October
Regional 2001-2020 average for October — NASA POWER, grid elevation 1773 m. Not a forecast.
Results history
| Year | Race | Finishers | Men's winner | Women's winner |
|---|---|---|---|---|
| 2025 | 6h | 12 | Mark Marzen · 69.201 km | Lindsey Welty · 59.545 km |
| 2024 | 6h | 9 | Dominick Rafiti · 65.983 km | Lauren Boldt · 67.592 km |
The field grew 33% between 2024 (9) and 2025 (12). 33% of the 2025 field were women.
DUV results for the 2025 edition (6h) — ranked runners 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
With trail terrain, choose a shoe with moderate cushioning for optimal performance.
Gear for this race
Chosen for this trail race.
- Trail Running Shoes Cushioning on trail that is still there in the last quarter.
- Race Nutrition Self-supported fuelling between aid stations.
- Hydration Vests Flask capacity without the bounce.
- GPS Watches Battery life first — an ultra outlasts most full-GPS modes.
Similar races
Other trail ultras of the same format.