Ultramarathon

OCC

OCC covers 60 km from Orsieres to Chamonix, delivering a sharp UTMB week mountain race with 3,500 meters of climbing and a fast 50K-final field.

Next raceThursday, August 27, 2026
Distance categoryUltramarathon
LocationOrsieres, Switzerland
Get alertsLast checked August 23, 2026

Quick facts

  • 50K final race in the UTMB World Series Finals.
  • Point-to-point route from Orsieres to Chamonix.
  • 60 km course with about 3,500 meters of climbing.
  • Fast, technical mountain format rewards strong climbing and descending.
Race-day forecast

OCC race-day forecast

Cloudy on race day · 21-27°C (69-81°F) · 14% rain · 8 mph wind

Race-day forecast for Thursday, August 27, 2026 in Orsieres, Valais, CH. Checked 11:51 PM GMT+2 race-local time. Data: Open-Meteo.

About the OCC

OCC is the Orsieres-Champex-Chamonix race in the UTMB Mont-Blanc week. It serves as the 50K final and brings a fast, technical mountain format to the same international stage as the longer UTMB races.

Course

The course starts in Orsieres and finishes in Chamonix after 60 km of alpine trail. The race lists 3,500 meters of climbing and a 14 hour 30 minute cutoff, making it short by UTMB-week standards but still demanding.

Race-day weather

Late August in the Valais and Mont-Blanc valleys can be mild, wet, or sharply colder at exposed points. The shorter distance favors speed, but weather and descent damage still matter.

Past OCC dates and results

YearDateStatusResults
2026Thursday, August 27, 2026Upcoming
2025Thursday, August 28, 2025CompletedOpen results
2024Thursday, August 29, 2024CompletedOpen results

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OCC FAQ

When is the OCC?

The 2026 OCC is on Thursday, August 27, 2026.

Does the OCC have live tracking?

Yes. Live tracking is available at live.utmb.world.

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