Sean O’Brien 50/50 Trail Race


Feb 05, 2022 at 5:00 AM

Sean O’Brien 50/50 Trail Race

1925 Las Virgenes Road

Calabassas CA, 91302


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Entry Fee $95
(Lowest or Early Registration)

Entry Fee 2 $150
(Highest or Late Registration)

Prize Money: no


  • 26.2M
  • 50K
  • 50M

Type: Ultra

Percent of the course on un-paved trails: 100%


The Sean O’Brien 50M/50k/26M was created after the original Ray Miller course had suffered a devastating fire in early May. The area was badly burned, and in my opinion needed time to heal. I was inspired to still bring a solid, competitive, and tough 50 mile/50k race to southern California in early winter. I also had a deep desire to still have this sort of race in the beautiful Santa Monica Mountains.


No photos available.


Past Event Dates

Held on Feb 05, 2022

Held on Sep 18, 2021

Held on Feb 01, 2020

Held on Feb 02, 2019

Held on Feb 03, 2018

Held on Feb 04, 2017

Held on Feb 06, 2016

Held on Feb 07, 2015

Held on Feb 02, 2013

Event Results

View 2014 Results