Folsom Lake Sweetwater Trail Run
Jan 23, 2027Folsom, CA38 mi, 50K +6
50K, 7 weeks before race day, 101 mi away
Marin Ultra Challenge
- 50K entry
- $160
- Aid stations
- 4
- Days to register
- 141
At a glance
- Date
- Mar 13, 2027
- Location
- Sausalito, California
- Distances
- 50 mi, 50K
- Elevation gain
- 11,000 ft
- Aid stations
- 4
- Registration
- Closes Mar 12, 2027, via ultrasignup.com
- Prize money
- $3,000 purse
- The top 3, male and female, finishers in the 50 Mile event will receive a custom trophy, as well as the following cash awards: ● 1st - $750 ● 2nd - $500 ● 3rd - $250
- Verified Oct 15, 2026 oninsidetrail.com
Listed from UltraSignup. Checked Oct 18, 2026.
Plan this race for free
4 aid stations are already loaded. Add cutoffs, pacing and the timeline your crew follows. Crew invites and race-day updates come with a Race Pass.
Build my planAbout this race
A premier Marin County long distance trail race delivering ample hills and sweeping descents. The 50 Mile has just about 11,000 feet of elevation gain, traversing the Marin Headlands, Stinson-facing Mt. Tamalpais and Muir Woods with a range of terrain from exposed fire-roads with incredible coastal and inland views to tight, technical single-track with redwood canopies.
Key dates
Registration closes
Mar 12, 2027
Race day
Mar 13, 2027
Pricing
50 Miler
Registration after Jan 26
$245
50K
Registration after Jan 26
$160
Email me updates about Marin Ultra Challenge
Registration openings and major changes, like a new date or a cancellation.
Aid stations
4| Station | Distance | Crew | Drop bags | Cutoff | Supplies |
|---|---|---|---|---|---|
Tennessee Valley AS Drop bags available. Gu Energy gels are not provided at this station because it is on GGNRA property. | 10.50 miles | -- | Gu Energy gelschewsStroopwafelstrail mix+14 | ||
Cardiac AS 50 Mile only. Drop bags available. | 19.80 miles | -- | Gu Energy gelschewsStroopwafelstrail mix+14 | ||
Cardiac AS 50 Mile only. Drop bags available. | 29.30 miles | -- | Gu Energy gelschewsStroopwafelstrail mix+14 | ||
Tennessee Valley AS 50 Mile only. Drop bags available. Gu Energy gels are not provided at this station because it is on GGNRA property. | 45.80 miles | -- | Gu Energy gelschewsStroopwafelstrail mix+14 |
Entry transfers
Can't race, or need an entry? Post it here so nobody has to ask if it's still available.
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Race planning
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