Marin Ultra Challenge

Marin Ultra Challenge

Our premier Marin County long distance trail race, the MUC delivers ample hills and sweeping descents. This year marks the 11th edition of this tour of some of Marin’s best trails. Meticulous effort went into the design of each course for the MUC; both distances are physically demanding (the 50 Mile has just about 11,000 feet of elevation gain) and exceptionally beautiful. The journey begins at the black sand of Rodeo Beach, then traverses the Marin Headlands, Stinson-facing Mt. Tamalpais and Muir Woods, exhibiting a range of terrain, from exposed fire-roads with incredible coastal and inland views to tight, technical single-track with redwood canopies. There is very little trail overlap, and Jim Vernon, from The Endurables and Hydrapak, spent hours and weekends developing these spectacular custom courses–we are super excited to show it off. You’ll quickly realize why Marin County has become the ultimate trail runner’s destination.

NOTE: Due to entry limitations by the GGNRA we will only be able to host a 50K and 50 Mile.

50/50 Challenge

Are you interested in participating in our third annual 50/50 Challenge (Monterey Ultra 50 Miler and Marin Ultra Challenge 50 Miler)? You will get on our 50/50 leader board and all finishers of the 50/50 get a commemorative back pack! Registration for the 50/50 Challenge is part of our Monterey Ultra Registration, the first race the the 50/50 Challenge.

Cancellation notice: to receive a credit must be 3 weeks out from either event you are withdrawing from).

Race Information

Location: Marin Headlands, Muir Woods & Mt. Tamalpais State Park
Date: Saturday, March 14, 2026
Events: 50K & 50 Mile
Bib Pickup: 5:00 AM - 7:00 AM
Start Times (Subject to change at the park's discretion):
50 Mile March 14 @ 6:00 AM
50K March 14 @ 7:00 AM
Timing: We will be partnering with our friends over at SF Run Company and ultralive.net for timing, aid station tracking and splits. There is a $3 fee added to race entry this year to bring this amazing feature to you!
Time Limit: There is a 14.5 hour time limit for the 50 Mile race. There is a 10 hour time limit for the 50K. All runners must be off the course by 8:30 PM
Parking: Free parking is available in the surrounding areas to the Start/Finish at Rodeo Beach. Runners may utilize the pullouts along Mitchell Road, along the beach, the annex lot below the Marine Mammal Center, and the Smith Road Parking Lot (Gerbode Valley Trailhead) along Bunker Road. The walk from the Marine Mammal Center lot to the Start/Finish is about 1/3 mile. The later you arrive the further you may have to walk to the Start/Finish, so please plan your arrival time accordingly.
Race Capacity: The Marin Ultra Challenge will have a capacity of 500 runners, across all distances.