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Miwok 100K ultramarathon

MAY 3, 2025 – 5:00 A.M.

Registration for the 100K and the Team Relay are full. See you on race day.

2025 Race Day runner tracking: Ultralive.net

RACE STARTING IN

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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 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 a proud member of 1% For The Planet & Leave No Trace and we work with GU Energy Labs to TerraCycle 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 Magda Boulet, RD at miwok100k@gmail.com.

Organizations we currently donate & support: Running For A Better Oakland |510 Hikers |Runners for Public Lands |The Coast Miwok of Marin |The Nomadic Adventure Club Ultra Fitness Beyond Imagination

Organizations we have donated in the past: The Edible Schoolyard Project |EatLearnPlay.org | Pinkathon/Breast Cancer Research Foundation

Miwok 100K ultramarathon Miwok 100K ultramarathon

Volunteers

If you’d like to be indispensable (and have a lot of fun without running all that way), contact RD Magda Boulet at miwok100k@gmail.com

Miwok 100K ultramarathon Miwok 100K ultramarathon

RD

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 took over as the Race Director in 2004, growing the event from 236 starters to its current field of 450. Magda Boulet took over as the Race Director in 2025.

questions?

Email RD Magda Boulet at miwok100k@gmail.com

Miwok 100K ultramarathon Miwok 100K ultramarathon

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 The Cost Miwok of Marin,  Running For a Better Oakland &  Runners for Public Lands

Miwok 100K ultramarathon

The May 3, 2025 Miwok 100K will be a UTMB 2026 Index Race at the 100K Level. 

WS100 2026 Qualifier