Drivers on Interstate 580 pass right below Dublin Hills Regional Park without noticing it. The East Bay Regional Park District park covers about 654 acres along a ridge that runs from Donlon Point, at its southern edge, toward Wiedemann Hill on private land to the north. The freeway borders it on the south, the Schaefer Ranch development on the southwest and the California Highlands neighborhood on the southeast.

Trails

The main route is part of the Calaveras Ridge Regional Trail, which is open to hikers, cyclists and horses. The park district says the trail starts near Schaefer Ranch and soon reaches grassland largely untouched since the 1800s. Wikipedia describes it as about 2 miles long, ending where the trail splits and meets private land. The Calaveras Ridge Trail doesn't reach the top of Donlon Point; a separate trail of about a third of a mile does.

A network of short trails called the Donlon Loop drops toward a housing development on Dublin Boulevard. Wikipedia notes these trails are too narrow for bikes and horses, and that trail users may not park in the development. There are no reservable campsites or picnic sites.

Getting there and hours

The trail staging area is just east of the intersection of Dublin Boulevard and Marshall Canyon Drive, according to the park district. In November and December, the park is open 8 a.m. to 4:30 p.m.

Wildlife

About 300 acres of the ridgelands are grassland. Coast live oak lines the edges of the watersheds, and bay laurel fills the drainages, where fallen bay leaves leave the ground nearly bare. Cooper's hawks, white-tailed kites, loggerhead shrikes and great horned owls live here, and golden eagles hunt over the grasslands. Ponds and seeps likely support California newts, tiger salamanders and Pacific tree frogs, and possibly the federally threatened California red-legged frog. Seasonal streams drain toward Palomares and Dublin creeks.

How it grew

The land was once ranchland. Wikipedia says the park opened in July 2010 with 520 acres. The district had bought about 400 acres for $2.3 million, and developers contributed 120 acres. In September 2015, the district bought a 362-acre piece of the Wiedemann Ranch on the park's northern edge to link Dublin Hills with the Bishop Ranch Open Space Reserve.