The Miwok 100K Trail Race is a 62.2 miles (100.1 km) long ultramarathon that takes place annually in southern Marin County, California, typically on the first Saturday of May.

Almost all of the course is on fire roads and single-track trails, first to the south of Stinson Beach and then to the north.

[2] The race, created by Kellie Sheehan and directed since 2004 by Tia Bodington, has been held every year since 1996 except 2020 and 2021, when it was canceled as a result of the COVID-19 pandemic.

[3] The event was shortened to 60K for 2013 due to fire restriction trail closures in the Mount Tamalpais area.

The course record (Rodeo Beach course) of 7 hours, 53 minutes, 19 seconds was set by Dave Mackey in 2008.