30K
Start7:00 AM
19.4Miles
3,894Ft Gain
2,217Ft High
Santa Monica Mountains · Trail Series
Sean O’Brien Trail Runs
Distances530K → 100K
Race DaySat, Jan 30, 2027Staggered starts
WhereMalibu Creek State ParkCalabasas, CA
TerrainSingletrack& fire road · well-marked
Must-read before race day
Athlete Guides
Start times, aid stations, cutoffs, parking, crew access and drop bags — everything you need, by distance.
Choose your distance
Tap Course Map on any distance to explore its route and elevation, then register on UltraSignup.
50K
Start7:00 AM
32.1Miles
6,719Ft Gain
2,273Ft High
Marathon
Start7:00 AM
27.2Miles
5,692Ft Gain
2,257Ft High
50 Mile
Start6:00 AM
49Miles
11,492Ft Gain
2,404Ft High
100K
Start5:30 AM
61.7Miles
13,179Ft Gain
2,408Ft High
The Race
Epic trail racing
Epic trail racing
in Calabasas
The Archive
Results & photos
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Course
Interactive map & elevation via HelloDrifterRegister