Regional Wilderness, Sunol, CA
A moderately strenuous hike will take you to the
top of Flag Hill, which is composed of layers of fossil-rich
sandstone formed some 13 million years ago. You'll enjoy
great views and good opportunities to watch birds and other
wildlife. Ambitious hikers may take an optional detour to
Indian Joe Cave Rocks.
Begin this hike by crossing Alameda Creek on the footbridge
near park headquarters. Turn left (downstream). After a
short distance, Flag Hill Trial will take off uphill, to the
right. The trail zigzags up the face of the hill (make sure
your hikers understand why it's important not to shortcut
switchbacks). After about a mile of rather steep uphill
hiking, you'll reach the top where you'll probably want to
take a good snack or lunch break. While on top, watch for
red-tailed hawks (the red upper surface of the tail is
visible when the hawk turns), turkey vultures (which hold
their wings in a slight "V" and teeter in flight), and maybe
even a golden eagle or falcon.
Continue your hike by dropping down the back side of Flag
Hill, turning right when you reach High Valley Road. High
Valley is a reservable hike-in campsite suitable for Boy
Scout troops. Return to the cars by way of Hayfield
For a more ambitious hike with a highlight the boys are sure
to love, take a detour to the Indian Joe Cave Rocks just
after you go through High Valley. Remind the boys about
rattlesnakes before letting them explore these huge jumbled
boulders. Return to the cars by way of the Indian Joe Creek
Trail. The detour will add about 0.7 miles to your total
distance, and is well worth it.
This hike is also nice in reverse (visiting the Cave
Rocks first, then Flag Hill), but going down the steep Flag
Hill Trail can be hard on the knees.
Historical and Natural
Sunol Regional Park area was inhabited by the Ohlone Indians
for about 4000 years. In 1797, when the mission was built at
Mission San Jose, most of the Indians moved to the mission.
The Indian camp was located on the same site as the Green
Barn and park office are now located.
In 1865, a family named Geary homesteaded the area and
built what is now the access road into the park, Geary Road.
Enough people moved into the area to establish a school.
The Sunol Valley has offered recreational opportunities
for several generations to campers. Campers from San
Francisco set up campsites in the Sunol Valley before the
turn of the century. The Gearys took part in encouraging
recreational use of the area by selling goods and providing
transportation to the campsites from the railroad station in
On the Fourth of July in 1903, a group of children
climbed a hill located north of the present park
headquarters, and planted a flag. The hill thereafter was
known as Flag Hill.
In the 1930's the land was purchased by a man named
Brinker. He built the barn at High valley, and perished
while fighting a fire on the property.
The East Bay Regional Park District purchased the land in
1959. Sunol Regional Park opened to visitors in 1960.
For more information, see this heading under the
Little Yosemite hike.
East Bay Regional Park District
2950 Peralta Oaks Ct.
PO Box 5381
Oakland, CA 94605-5369
(510) 635-0135 (General Info)
(510) 636-1684 (Group camping reservations)
(510) 862-2244 (Sunol Regional Wilderness Headquarters) Call
this number to reserve the "School Camp" for your group.
Distance: 3.5 miles round trip
Time: Allow 3 to 4 hours
Elevation gain: 960 feet
Grade: Starts with a steep up-grade and ends with a moderate
Suggested age: Webelos
Suggested season: Late spring to late fall.
AAA "Alameda-Contra Costa Counties."
EBRPD folder "Sunol Regional Wilderness", available at the
park and at most EBRPD Visitor centers and park
By Car: From Fremont area drive north on Highway 680 to
Calaveras Road. Turn right on Calaveras and proceed about 4
miles and turn left onto Geary Road, which leads into the
From Oakland area, drive east on Highway 580 and follow
signs to Tracy to junction with Highway 680. Go south on 680
to Calaveras Road / Highway 84 exit, just south of the town
of Sunol. Turn Left on Calaveras Road. Go about 4 mile and
then turn left onto Geary Road (after Welch Creek Road)
which leads to the park. After passing the kiosk at the park
entrance, turn left and park near the entrance.
Picnic areas (tables, grills, water, restrooms)
Reservable group campsites
Reservable family campsites
Horses for hire
Hiking and bicycling trails
Remember money for parking
Poison oak is abundant
Rattlesnakes share the park with visitors
Exercise caution when hiking downhill on steep grades
Sunol Regional Park shares the area with the San Francisco
Water District and private land owners. Please respect the
"NO TRESPASSING" signs.
Activity suggestions and other
Sunol Regional Park offers an excellent naturalist program.
Make reservations and allow time for the Scouts to explore
the flora, fauna, and natural environment. After the hike
your group might enjoy a barbecue at one of the picnic
Forester, Geologist (Sunol has some great rock formations),
Pack 268 Home
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Coyote Hills |
Flag Hill | Hoot
Owl | Little
Redwood Creek |
Rodeo Lagoon |
Sycamore Grove |