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Sean O'Brien 100K

Calabasas, United States • 31 Jan 2026

Event details

Sean O'Brien is a trail running event held Saturday, Jan 31, 2026, in Calabasas, California. The venue address is 1925 Las Virgenes Road. The event includes multiple race distances and is listed as a qualifier for the Western States 100 for the 100K distance.

Distances and registration

  • 100K
  • 50 Miler
  • 50K
  • 26.2 (marathon)
  • 30K

Registration closes Monday, Dec 15 at 11:59 PM PT. Visit the organization's website for the most recent information.

United States California Calabasas

Race information

Website Registration
100 km
100k
50 mi
50 Miler
50 km
50k
26 mi
26.2
30 km
30k
Visit the organization's website for the most recent information.
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