Marin County Parks and Open Space Department

Old Saint Hilarys DetailThe land immediately surrounding this small chapel was set aside as a historical landmark in the ‘50’s, as was the slope below it, which came to be known as the John Thomas Howell Botanical Garden, in honor of the author of the venerable Marin Flora. But the land above and below these parcels was slated for development and didn’t pass into public hands until the 1990’s.

Today, the 122 acre preserve is one of only two places to see the extremely rare Tiburon jewelflower. This odd member of the mustard family has such dark maroon flowers that they appear to be nearly black, thus earning the scientific name Streptanthus glandulosus ssp.niger. These flowers may usually be seen from mid-May to mid-June along the Vistazo Fire Road, which traverses the lower portion of the preserve. Please stay off of the small trails that lead uphill from this fire road, all of these paths are causing damage to this fragile habitat and the unique plants found here. Views from the top of the hill (where the preserve adjoins the Tiburon Uplands County Park) are fabulous. To access the upper part of this preserve use the trailhead at the end of Lyford drive, or the one at the end of Heathcliff drive. One can sit atop this windswept slope and fully appreciate how lucky we are to have saved this slice of unique habitat for public enjoyment. 


North access: from Hwy 101 in Mill Valley, take the exit for Tiburon Blvd (Hwy 131) east 3.5 miles. Turn left onto Lyford Dr, MCOSD gate is at the end.

South access: from Hwy 101 in Mill Valley, take the exit for Tiburon Blvd (Hwy 131) east 3.5 miles. Turn left onto Lyford Dr, right onto Vistazo West St, and follow to the end (dead end).

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

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Birds, Wildflowers


24 hours

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