Overview
Rancho San Antonio Open Space Preserve sits at the eastern base of the Santa Cruz Mountains, straddling the boundary between Cupertino and Los Altos Hills in the heart of Silicon Valley. Managed jointly by the Midpeninsula Regional Open Space District (MROSD) and the County of Santa Clara, it covers roughly 4,000 acres and offers one of the most accessible wilderness experiences in the Bay Area.
The preserve draws a wide range of visitors — serious hikers tackling the climb to PG&E Trail and Rogue Valley, families visiting Deer Hollow Farm, trail runners, and birdwatchers scanning the seasonal ponds and oak woodlands. Elevation within the preserve ranges from the flat valley floor near the main parking area to around 2,000 feet on the upper ridgeline, giving trails genuine variety.
Despite sitting minutes from major tech campuses and suburban neighborhoods, the preserve feels genuinely wild in its upper reaches. Black-tailed deer, coyote, wild turkey, and — occasionally — mountain lion are all recorded here. The combination of proximity to population centers and authentic open space makes Rancho San Antonio one of the most-visited open space preserves in the entire MROSD system.
Before You Go
Permits and Fees
As of the time of writing, trail access is free. The main County parking lot at the Cupertino trailhead typically charges a fee; verify the current rate on the Santa Clara County Parks website before your visit, as fees and payment methods can change. Overflow parking at nearby Regnart Elementary School (when available on weekends) has historically been managed through a free shuttle — confirm this arrangement on the MROSD website before relying on it.
Reservations
During peak periods — primarily weekends from spring through fall — the main parking lot fills very early, often before 8 a.m. MROSD has at times implemented a parking reservation system or encouraged the shuttle option. Check the official MROSD site (openspace.org) for current access advisories before your visit.
What to Bring
- Plenty of water; there is no potable water available on upper trails
- Sunscreen and a hat; the upper trails offer little shade in summer
- Layers — fog can linger in the morning and winds pick up on the ridge
- Trail map (downloadable from MROSD's site or available at the trailhead kiosk)
- Dog owners: leashes are required in most areas; verify which trails permit dogs before going
Getting There
By Car
The main trailhead is located at 22500 Cristo Rey Drive, Cupertino, CA. From Interstate 280, take the Foothill Expressway/Foothills Boulevard exit and head south, then turn right on Cristo Rey Drive. The County parking lot is at the road's end. GPS navigation to this address is reliable.
By Transit
The preserve is not directly served by frequent transit, but VTA bus routes serve parts of Cupertino and Los Altos. From there, the trailhead is roughly a mile walk or short rideshare trip. Verify current VTA routes and stops at 511.org before planning a transit-based trip.
By Bicycle
The paved multi-use trail connecting the parking area to Deer Hollow Farm is accessible by bicycle. The Cristo Rey Drive approach is bikeable from several surrounding neighborhoods and bike lanes on Foothill Expressway. Upper trails are designated for hikers only in most sections; check the MROSD trail map for current bicycle-permitted routes.
Getting Around
Navigation within the preserve is straightforward for most visitors. A flat, paved, multi-use path (approximately 1.6 miles) runs from the main parking area to Deer Hollow Farm and is suitable for strollers, wheelchairs, and cyclists. From the farm, a network of unpaved trails fans out toward the upper preserve.
Trail junctions are signed, but carrying a downloaded trail map is strongly recommended once you move beyond the paved path. Popular loops include the Rogue Valley Trail and the PG&E Trail, which climbs to open ridgeline with views across the Bay. Many visitors combine the lower farm area with one upper loop to make a satisfying half-day outing.
Cellular coverage is generally adequate on the lower trails but can be patchy in the upper canyon areas. Download maps offline before entering the preserve.
Things to See & Do
Hiking
The preserve has over 24 miles of trails ranging from the flat paved path to steep ridge climbs. The Rogue Valley Loop (roughly 5–6 miles with elevation gain) is a popular intermediate outing with creek crossings and oak woodland. The PG&E Trail extension offers the most dramatic Bay-wide views and a significant workout.
Deer Hollow Farm
Operated by the City of Mountain View, Deer Hollow Farm is a working demonstration farm and nature center located about 1.6 miles from the main trailhead along the paved path. It features farm animals, gardens, a historic log cabin, and educational programs for children. Opening days and hours vary by season; verify current schedules with the City of Mountain View's website before visiting, as it is closed on certain days.
Wildlife Watching
The preserve's riparian corridor, oak woodlands, and grasslands host a notable diversity of birds, including acorn woodpeckers, red-tailed hawks, and various waterfowl near seasonal ponds. Mammals including mule deer, coyote, bobcat, and wild turkey are regularly observed. Early morning visits on weekdays dramatically improve wildlife encounter rates.
Trail Running
Rancho San Antonio is one of the Bay Area's most popular trail running venues. The varied terrain and well-maintained trails attract runners of all levels. Be aware that the paved lower section can be very congested on weekend mornings and trail etiquette — yielding to hikers, controlling speed near blind corners — is important.
Food & Drink
There are no food or beverage vendors within the preserve. Bring all food and water you expect to need; water is not reliably available on the trail system. Picnic areas exist near the parking lot and at Deer Hollow Farm.
Cupertino's main commercial corridor along Stevens Creek Boulevard, roughly 10–15 minutes by car from the trailhead, has a wide range of cafes, fast-casual restaurants, and grocery stores. The downtown areas of Los Altos and Sunnyvale are also a short drive away. Many visitors plan a post-hike meal in one of these nearby towns.
Practical Information
Facilities
Restrooms are located at the main parking lot and at Deer Hollow Farm. There are no restroom facilities on the upper trails.
Dogs
Dogs on leash are permitted on some trails but not all. The paved multi-use path and certain dirt trails allow leashed dogs; others are off-limits to protect wildlife. Confirm the current dog-permitted trail map on openspace.org before your visit.
Leave No Trace
The preserve is heavily used. Pack out all trash, stay on designated trails, and do not pick plants or disturb wildlife. Fires and camping are not permitted.
Emergency Contact
For trail emergencies within the preserve, call 911. The MROSD ranger patrol is also active in the preserve; contact information is posted at the main trailhead kiosk. Verify current ranger contact details on openspace.org.
Safety
Mountain lion activity has been documented in the preserve. The MROSD posts advisories at trailheads when recent sightings occur. Standard precautions apply: hike in groups, keep children close, do not run if you encounter a lion, and make yourself appear large while backing away slowly.
Rattlesnakes are present, particularly on sunny, rocky sections of trail in warmer months. Stay on the trail, watch where you step and place your hands, and give any snake you encounter space to move away.
Poisonous oak is widespread throughout the preserve, especially along riparian areas. Learn to identify it (clusters of three shiny leaflets) and stay on designated trails. Wash exposed skin thoroughly with soap and water if contact occurs.
Summer afternoons can be significantly hotter than the Bay Area average on the south-facing upper slopes. Start early, carry more water than you think you need, and be willing to turn around if conditions feel unsafe.
