Los Trancos Open Space Preserve is a 274-acre area located in the Santa Cruz Mountains above Palo Alto. This is an ideal spot to learn about earthquake geology. The San Andreas Fault, one of the world's longest and most active faults, splits the preserve.
The Preserve is situated at about 2,000 feet and always has fresh air scented with pungent bay leaves, sweet grass and damp woods. Here, visitors will find a pleasant environment of rolling grassland knolls alternating with oak woodland and cool shaded forest. On a clear day, one can spot the gleaming skyscrapers of San Francisco and pick out Mt. Diablo across the bay.
Visitors can hike the easy 1.5-mile trail and learn how the mighty San Andreas Fault has shaped our landscape. Download a guide.
Discover seven points of interest along this 2.5-mile long trail, which takes you through grassland, chaparral, and mixed evergreen forest. This walk will have a total elevation gain of about 500 feet and will take about one to three hours, depending on your pace.
Preserve Highlights & Features
San Andreas Fault Earthquake Trail
The San Andreas Fault Earthquake Trail is an ideal spot to learn about earthquake geology. Visitors can hike the easy 1.5-mile self-guided interpretive trail which gives visitors a chance to learn more about the lead player on California's geology.
Here are some of the plants and animals that other visitors have observed at this preserve and recorded in iNaturalist. Protected species may be excluded and some species may not yet have been observed. Help improve iNaturalist by adding your observations to the Midpen Biodiversity Index project
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Know Before You Go
Preserve regulations help provide a safe, enjoyable visit while protecting sensitive areas and wildlife.
Share the Trail
Use designated trails to avoid damage to natural resources and prevent injury.
Avoid blocking the trail. Step aside to allow others to pass .
Whether you’re walking or biking, always yield to equestrians.
Leave no trace. Pack out what you pack in. Most preserves do not have trash cans. Littering is prohibited.
Abuses of trail etiquette should be brought to the attention of a ranger or call the Midpen main office at 650-691-1200.
- No current closures
Los Trancos Preserve Parking Lot (30 spaces): The preserve's entrance is on Page Mill Road, 7 miles west of Highway 280 and 1.5 miles east of Skyline Boulevard. Parking is available for 20 vehicles. Additional parking and restroom facilities are available at the Monte Bello Open Space Preserve parking area, located directly across Page Mill Road.
- Equestrians: Horses are allowed on designated trails (marked on map). Helmets are recommended for all equestrians. For more information visit the Equestrian Access page.
- Bicyclists: Bikes are NOT allowed in this Preserve. For information on preserves open to bikes visit the Bicycle Access page.
- Dogs: Dogs are not allowed in this Preserve. For information on dog-friendly preserves visit the Dog Access page. In accordance with the Americans with Disabilities Act, Midpen accommodates service dogs in preserves wherever we allow public access.
- Fires are prohibited in preserves.
- Plants & Wildlife: Please leave undisturbed. If you encounter wildlife during a visit, do not approach, startle or feed it. Although wild animals are generally fearful of humans and will run away, some wildlife can be dangerous.
- Smoking is prohibited in preserves.
- Water Areas: Swimming, wading or engaging in any water-contact activity is prohibited.
- Weapons are prohibited in preserves.
A general access permit is required for any activity or event that:
- may be attended by twenty (20) or more people; OR
- would restrict the use of any part of Midpen lands by members of the public; OR
- requests or requires a fee be paid or a donation made for participation. This includes events where the fee is in the form of a mandatory purchase, such as a t-shirt.
Midpen trails and facilities are generally very safe. However, you are entering an environment where there are some naturally occurring hazards. Reasonable caution and common sense should be utilized when venturing into any outdoor environment.
- Do not leave valuables in your vehicle! Lock your vehicle and store valuables out of sight or take them with you on the trail.
- Travel in groups of two or more. Two of more people can assist each other in the event of an accident or emergency.
- Dress for the environment. Temperature changes can be occur and you should dress in layers appropriate for the location, time of year and planned activities.
- Carry water with you. Drinking water is not available at most Midpen preserves so you should bring your own. Two quarts per person per two hour hike is recommended.
- Apply sunscreen and drink plenty of water prior to and during your outdoor activities.
- Be aware that cell service is very sporadic on the preserves.
Be Prepared and Aware
Plan ahead before you leave. Check regulations and weather, download a map, pack water and first aid.
Know your limits and take safety precautions.
Rattlesnakes are native to this area and are especially active in warm weather.
Poison oak grows on most preserves: Learn to identify and avoid it in all seasons.
Ticks are present in this area and may carry diseases.
Mountain lions are a natural part of this region’s environment and are occasionally seen.
In Case of Emergency
If you experience an emergency (fire, accident or other immediate threat to life or property), call 911. For nonemergencies, call 650-691-1200.
Once part of a 13,300-acre ranch in the nineteenth century, the land that was to become Los Trancos Preserve was purchased in the early 1900s by Louis Oneal, a San Jose attorney and state senator who raised horses and owned the nearby O&O Breeding Stables. The property changed hands in the 1950s, and in the 1960s Palo Alto ran water and power lines to it, in anticipation of residential development. The Livingston-Blarney report detailing the high cost of providing city services to the foothills stopped a proposed subdivision. The District acquired most of the property in 1976.
The 1.5-mile San Andreas Fault Trail was established in 1977 with volunteer assistance from former Foothill College geology professor Tim Hall and his students.