The Hassler Health Farm served tuberculosis patients in an era when fresh air and elevation were considered therapeutic. By the time the Midpeninsula Regional Open Space District purchased the land in 1983, the sanitarium's era had long passed. Buildings were demolished two years later, and a systematic effort to remove non-native plants began. Most of the introduced species have been cleared, though traces of the sanitarium landscape persist along the Hassler Trail, where retaining walls and stairs appear among the oaks like archaeological fragments. The transition from medical facility to public preserve was neither dramatic nor swift, but the result is a landscape where human infrastructure has been almost entirely absorbed back into the hillside.

Pulgas Ridge hosts the headwaters of Cordilleras Creek, one of the lesser-known waterways draining the eastern slopes of the Santa Cruz Mountains toward San Francisco Bay. The preserve covers terrain with about 500 feet of elevation change, enough to create distinct habitat zones as you climb from the valley floor to the ridgeline. Lower trails pass through California mixed evergreen forest and oak woodlands, while higher elevations offer views across the Bay to the East Bay hills. The understory is home to banana slugs, Coast Range newts, and a variety of birds. Trail names honor local contributors and, in one case, the dusky-footed woodrat, a rodent that builds elaborate stick houses on the forest floor.

In a region where trail access rules can feel labyrinthine, Pulgas Ridge keeps things simple. The preserve is open from dawn to half an hour after dusk. All trails are open to hikers and dogs, with equestrians permitted on some routes. Bicycles and horses are restricted on certain trails. The preserve includes a large designated off-leash dog area, a rarity among Midpeninsula Regional Open Space District lands and a significant draw for dog owners who want more than a fenced park. Outside the off-leash zone, dogs must be leashed, but the mere existence of such an area on preserved open space reflects a pragmatic approach to balancing conservation with community recreation.

The preserve is bounded to the north by San Francisco watershed land, to the west by Skyline Boulevard, and to the south by Huddart County Park. The area east of the park is private property. Access comes from a parking area in Huddart County Park off Kings Mountain Road or from a trailhead on Skyline Boulevard. Standing on the higher trails and looking east, you see the suburban grid of the Peninsula stretching toward the Bay. Looking west, the forested slopes drop away toward the coast. The ridge occupies the boundary between these two landscapes, urban and wild, and the preserve holds a space where both can coexist on six miles of well-marked trail.