Sausalito, CA (Rodeo Beach)

Avg Temps f.


Gain/Loss in ft

10,550/10,550 (50m)

6,300/6,300 (50k)

ft/mile gain

211 (50m)

203 (50k)

Highest Elev.

1775ft (50m)

1024 (50k)


6:30am (both)


Varying, mainly single-track trail

Time Limit

14.5 hours (50m)

10 hours (50k)



Furthest Aid

6.6 (50m)

6.9 (50k)


Summary: Starting and finishing at Rodeo Beach, all three distances of the The Marin Ultra Challenge, the 25k, 50k, and 50m, all feature lots of challenging elevation changes. The races have a range of terrain, from exposed fire-roads to technical single track in the redwood trees. Super beautiful scenery if the weather is right, with great course support.

Lessons Learned from Race Reports

  • Must start the race with a headlamp and pick one up again if you think you’ll run past 6:30pm
  • Beautiful race but the elevation change is no joke, not just the gain, but the downhills as well, as you’re constantly going either up or down, some sections more runnable than others
  • Trail may be a bit congested at the start with both 50k and 50m starting on an uphill, with some sections with stairs
  • Climb in the middle of the race for the 50 milers up to Willow Camp is the most challenging – steep without switchbacks and have to run some roads out of Stinson Beach to get to the trails again
  • Likely lots of day hikers out on the trails, so be aware of other trail users and pay attention to course markings since hikers are going different ways, and there’s a point which the 50m and 50k split
  • Even though the courses have main climbs and descents, that doesn’t mean there won’t be smaller climbs and descents along the way
  • If it’s wet and windy, that can be especially challenging, as a lot of the course is exposed and not in the trees
  • Bring a change of clothes for afterwards, especially if there’s any moisture, as you’ll cool down fast
  • Weather likely to change a lot leading up to the race, so have options, especially layers, for the day of


Total gain/loss: 10,550/10,550 (50m), 6300/6300 (50k)

Ft/mile gain: 211 (50m), 203 (50k)

Total climbs:

50m: 9 main climbs and descents ranging from 600-1800 feet with 3 climbs of 1,000+ feet and 1 climb of 1800 feet

50k: 6 main climbs and descents ranging from 500-1100 feet with 1 climb of 1,000+ feet and 4 climbs of over 600 feet

Course Maps (both) Miles 1-15 and 39-50 and Miles 15-39 /Elevation profile (both)

Aid stations

Total aid stations:

50m: 9

50k: 5

Furthest distance apart:

50m: 6.6

50k: 6.9


50m: Miles 5.8, 10.5, 14.7, 19.8, 23.4, 29.3, 35.9, 40.8, 45.8

50k: Miles 5.8, 10.5, 14.7, 21.6, 26.6

50m Aid station chart

50k Aid station chart

What’s available: A variety of glycogen-replenishing, electrolyte-replacing products, which may include: Gu Energy gels and chews, Larabars, trail mix, pretzels, potato chips, Oreo cookies, Pop Tarts, boiled potatoes with salt, Coke, Mountain Dew, Ginger Ale, water, Tailwind, PB&J sandwiches, M&M’s, Mike & Ike’s, salt tablets, and tangerines. Aid stations are also equipped with general first aid items but no anti-inflammatory medicine.

Crew access

Access Locations: All aid stations

Crew instructions/directions: Crews must abide by posted parking rules. There is no parking at the Deer Park Aid Station (mile 35.9 of 50m). Crew must hike 1/2 miles to reach the Cardiac Aid Station (in 50m).


50m: Pacers may join runners at any time after their second pass through Cardiac Aid Station, mile 29.3.

Race qualifiers

50m: 4 UTMB Points

50k: 3 UTMB Points

Race reports




Strava activities and GPX files



Race Website