Grindstone by UTMB 100M
Grindstone by UTMB 100M tackles 104 miles and nearly 21,000 feet of climbing through Virginia's technical Allegheny Mountains each September.
Every link above goes to the race, its timing provider, or an official registration partner. Last checked July 22, 2026.
Quick facts
- Friday evening start on September 18, 2026
- 104 miles with 20,997 feet of climbing
- Natural Chimneys Park start and finish
- Thirty-six-hour maximum time
About the Grindstone by UTMB 100M
Grindstone 100M is the longest race at the Virginia UTMB World Series weekend. Its Friday evening start, 36-hour limit and 104-mile mountain course create a distinct overnight endurance event.
Course
From Natural Chimneys Park, the course covers about 104 miles with 20,997 feet of gain. Long climbs on Wild Oak and technical Appalachian trail make hiking strength as important as runnable speed.
Race-day weather
September in western Virginia can bring humid warmth in valleys and cooler, windy conditions on ridges overnight. Rain can quickly make the technical trail slick.
Past Grindstone by UTMB 100M dates and results
| Year | Date | Status | Results |
|---|---|---|---|
| 2026 | Friday, September 18, 2026 | Upcoming | — |
Grindstone by UTMB 100M FAQ
When is the Grindstone by UTMB 100M?
The 2026 Grindstone by UTMB 100M is on Friday, September 18, 2026.
How do I register for the Grindstone by UTMB 100M?
You can register for the Grindstone by UTMB 100M at grindstone.utmb.world.
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