While nine of the 26 parks that make up the Mid-Peninsula Open Space Preserve system allow dogs on-leash, Pulgas Ridge Preserve is the only one that has a designated off-leash area. This 16-acre off-leash area alone is worth the drive—only about 20 minutes south of San Francisco—but all the trails are well-maintained and provide fabulous views.
The 293 acres that comprise this preserve were formerly a tuberculosis sanitarium owned by the City of San Francisco, the Hassler Health Farm. MROSD purchased the land in 1983 and the sanatorium buildings were demolished in 1985 but some old retaining walls remain off Hassler Trail. As part of this project, most non-native plants have been removed.
Use the Google Maps link above for driving directions to the Edmonds Road Parking lot. Take the Blue Oak Trail .4 miles to the off-leash area. After a romp, take the Hassler Trail to the Dusky Footed Woodrat Trail (how could you resist a trail with this moniker?) to the Polly Geraci Trail back to your car.