Course
A trail race based at Malibu Creek State Park in Calabasas, with all distances starting and finishing there and sharing a network of aid stations. Five distances are run: 100K at 5:30am, 50 mile at 6:00am, and the 50K, marathon and 30K all at 7:00am.
100K100 km
50 Mile50 mi
50K50 km
Marathon42.2 km
30K30 km
Key dates
- !RegistrationOpen now
- !Entries closeTue 1 Dec 2026 · in 6 weeks
- ★Race daySat 30 Jan 2027
Date confirmed with the organiser · entry window checked by RunCalendar
About
Sean O'Brien Trail Runs is a Coastal Trail Runs ultra series through the Santa Monica Mountains near Malibu, offering 30K, 50K, marathon, 50-mile and 100K distances on rugged singletrack with steep climbs and coastal-range views.
Your next race, seen from above.
Save Sean O'Brien Trail Runs to your season and RunCalendar reminds you the morning entries open and before they close. Free on iPhone, no account needed.
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Save Sean O'Brien Trail Runs to your season and RunCalendar reminds you the morning entries open and before they close. Free on iPhone, no account needed.
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