Marin County Parks and Open Space Department

This 403 acre preserve was added to the MCOSD system in 2000. It incorporates the south-facing slope above the western end of the San Geronimo Valley. Together with the Gary Giacomini and Roy’s Redwoods Preserves, these lands constitute a major portion of the Lagunitas Creek watershed, so management practices in this area involve protecting and improving habitat for the endangered coho salmon.

At the western end of the preserve is a steep slope that includes significant areas of exposed serpentine. The unique soil derived from this mineral supports many rare plants, including serpentine reedgrass, Tiburon buckwheat, and Tamalpais lessingia. The French Ranch Fire Road allows access to the ridge overlooking the valley; it runs alongside a deep, forested canyon that is a haven for wildlife among the plentiful Douglas fir, redwood, oak, and tanoak trees. The fire road that runs along the ridge passes in and out of private property along the border of the preserve. Please be respectful of our neighbors if you use this road to access or exit this preserve.


From Hwy 101 in Larkspur, take the exit for Sir Francis Drake Blvd west 8.6 miles. Turn right at Nicasio Valley Rd. Gate is approximately 0.5 miles up on the right.

Visit,,, or dial 511 to find out about alternative transportation and public transit options from your location.

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Birds, Geologic Interest, Redwoods, Wildflowers


24 hours

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