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  • Miwok 100K trail
    Miwok 100K Ultramarathon runner on the Marin County coast of California
  • Miwok 100K trail
    Miwok 100K Ultramarathon runner on the Marin County coast of California
Miwok 100K ultramarathon

MAY 3, 2025 – 5:00 A.M.

Registration Opens at 6:00 a.m. PST on November 9, 2024 at
+NEW: Miwok 100K Team Relay

[see Registration page for full details]



The Miwok 100K is one of the most beautiful and iconic trail ultramarathons in the world. The course is hilly (11,800 feet of gain) but runnable, with spectacular views of San Francisco and the Golden Gate Bridge, Sausalito, Mount Tamalpais, the ancient redwoods and the Point Reyes National Seashore.

The course features single-track trails and dirt roads with about a mile of paved road. The race is very competitive at the front, and a rewarding challenge for all. Less than an hour from San Francisco, the Start/Finish is in the town of beautiful Stinson Beach, nestled against Mount Tamalpais, with its excellent cafés, a small market, lodging, and more.

Course marking is excellent, and you’ll be supported by some of the best volunteers on a race course anywhere. We hire professional medical for all aid stations for those occasional skinned knees and such. Our 2023 runners will receive ultra-specific goodies along with their finisher’s award.

Sustainability. Diversity. Community.

The Miwok 100K has focused on sustainability for over a decade, and is an industry leader in recycling, food composting, and waste minimization. The race has been cup-less since 2013. Leftover food is donated to a local shelter.

We are now a proud member of 1% For The Planet in addition to working with TerraCycle to recycle all our race nutrition packaging.

In 2020, we launched the Miwok 100K Diversity Initiative, to further enhance inclusion of under-represented demographics at the Miwok 100K. If you or your company would like to be a part of this initiative, contact Tia Bodington at

Since 2008, we have donated to local organizations that help disadvantaged and hungry children, including The Edible Schoolyard Project and, providing food and support to kids in the Bay Area. We also donate to Pinkathon/Breast Cancer Research Foundation, Running For A Better Oakland, and other local groups.

Miwok 100K Trail Race volunteer dressed as pirate and directing runners Miwok 100K Trail Race volunteer dressed as pirate and directing runners


If you’d like to be indispensable (and have a lot of fun without running all that way), click here to volunteer.

Volunteer Questions?
Email Co-RD Magda Boulet at

Miwok 100K Miwok 100K

25 years

The Miwok 100K was founded in 1996 by Kellie Sheehan. That first race, held on May 6, 1996, had about 70 intrepid souls on the start line. Tia Bodington has directed the race since 2004, growing the event from 236 starters to its current field of 450. Magda Boulet joined the event as Co-Race Director in 2023.


Email Co-RD Tia Bodington at

Quicksilver Running Club runner Quicksilver Running Club runner


sunset at Point Reyes sunset at Point Reyes


NYT best-selling author, Dean Karnazes, concludes his 2021 book, A Runner’s Highwith a chapter on the Miwok 100K.

The Miwok 100K is featured in the 2019 The Rise of the Ultra Runners, by award-winning author Adharanand Finn.

Glenn Tachiyama’s fantastic .

RootsRated’s Epic NorCal Trail Races 

sponsors & partners

Our thanks to the wonderful sponsors and vendors who will be providing cool stuff to our runners. More to come! We’d also like to thank the California State Parks, the Golden Gate National Recreation Area, and Point Reyes National Seashore for their work to manage and maintain the trails on which we love to run!

This year, our donations go to Running For a Better Oakland and Runners for Public Lands.

Miwok 100K ultramarathon

The May 4, 2024 Miwok 100K will be a UTMB 2025 Index Race at the 100K Level. 

WS100 2025 Qualifier