Grindstone 50K is the 50.0km trail race at Grindstone Trail Running Festival by UTMB 2027 (Natural Chimneys Park, United States). The race starts on September 25, 2027 at 07:00 AM. It starts in Natural Chimneys Park. The time limit is 9 h.
Run easy on the first mountain, then go all out on the second.
The course climbs 1550m+. With 31m/km of climbing, this is a rolling, mostly runnable course. By gradient, 32% of the distance is uphill, 29% downhill and 39% flat. The longest climb runs 8.1km at an average 7.3% grade (588m of vertical). The longest descent runs 14.8km at an average 6.1% grade (899m of vertical). The steepest climb averages 29.7% over 0.3km. The steepest descent drops at 20.8% over 0.5km. Surface: 57% trail, 20% road, 13% smooth, and 10% extreme.
The course also passes close to Sand Spring Mountain (1137m).
Poles bring little benefit here: only about 3.0km of pole-friendly terrain.
Quad damage risk is low (index 15 of 100): a few descents worth noting, none of them decisive.
This page has a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Grindstone 50K.
Other distances of Grindstone Trail Running Festival by UTMB 2027Grindstone 100M (167km)·Grindstone 100K (100km)·Grindstone 21K (21.0km)
Other editions of Grindstone 50K2026·2025
Official websitegrindstone.utmb.world