At the end of Geary Road outside the town of Sunol, the East Bay hills feel a long way from the freeway. The East Bay Regional Park District's Sunol Wilderness Regional Preserve covers 6,859 acres of oak woodland, grassland and creek canyon south of Pleasanton and east of Fremont. Cattle still graze much of it.

The Alameda Creek Overlook

The park's signature destination is the scenic gorge on Alameda Creek about two miles upstream from the visitor center. The park district now calls it the Alameda Creek Overlook; it was formerly known as Little Yosemite. The land belongs to the San Francisco Water Department and is open through a lease agreement, so stay inside the boundary signs.

Swimming and wading are not allowed in Alameda Creek or anywhere else in the preserve, because endangered species live in the water. The Canyon View Trail, about 1.4 miles, runs through Jacob's Valley to the gorge.

Other trails

The 1.26-mile Flag Hill Trail climbs steep switchbacks to views of the Alameda Creek watershed and Calaveras Reservoir. The gentler Indian Joe Creek Trail passes the Cave Rocks and includes a one-mile self-guided nature loop; pick up the booklet at the visitor center. Wikipedia notes that Cave Rocks is popular with rock climbers. The 3.9-mile Maguire Peaks Loop has views of San Antonio Reservoir and Mount Diablo and needs a separate parking permit on Welch Creek Road on weekends and holidays.

Sunol is also on the Ohlone Wilderness Trail, which runs from Mission Peak near Fremont to Del Valle near Livermore. The park district says that as of Jan. 1, 2026, hikers no longer need an Ohlone permit, but overnight backpacking still requires reservations at least two business days ahead.

Wildlife

Golden eagles, red-tailed hawks, acorn woodpeckers and black phoebes are common along Alameda Creek, and the district says birders often log 20 to 40 species in a morning. Wikipedia notes the park supports one of the largest breeding populations of golden eagles, which feed on the plentiful ground squirrels. Mountain lions are seen only occasionally. Sandstone outcrops hold fossils from an ancient seabed. Spring wildflower season usually runs from about the end of March to early May.

Hours, parking and the visitor center

Parking is $5 per vehicle on weekends and holidays. From Nov. 1 to March 7, the park is open 8 a.m. to 5 p.m. The visitor center is open Fridays from 9 a.m. to 1 p.m. and on weekends and most holidays from 8:30 a.m. to 4 p.m. Inside you can meet animal ambassadors, among them a gopher snake, a western pond turtle and a tarantula, and see a herbarium of more than 600 plant specimens. There is no drinking water in the park.

Related: where to spot tarantulas at Sunol, Del Valle and Mount Diablo and the Sunol Water Temple down the road.