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Sean O'Brien 100K

Name: Sean O'Brien 100K
Start: 2027-01-23
End: 2027-01-23
Location: Calabasas

Calabasas, United States • 23 Jan 2027

Sean O'Brien 100K/50M/50K/26.2/30K - January 31, 2026

This event is a set of trail races held in Calabasas, CA, with a listed venue at 1925 Las Virgenes Road. The program for the date includes multiple distances on trail terrain and references course viewpoint photos such as Mile 7 and Mile 15 and general trail views.

The 100k distance is designated as a 2026 WS100 qualifier. The event appears as part of a trail race series and includes marathon and shorter ultramarathon options. The page for the event lists maps and directions for the location.

Distances offered include:

100k
50 mile
50k
Marathon (26.2)
30k

The description presents factual details about location, offered distances, and the qualifier status for the 100k. No start or finish times are provided in the available information. 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

Marathon

30 km

30k

Visit the organization's website for the most recent information.

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