Coal Mine Ridge,
Portola Ranch Homeowner's Association,
San Mateo County
In brief:
3.1 mile easy loop is a nearly level trip through woods and oak grassland.

Distance, category, and difficulty:
This 3.1 mile loop hike is easy, with about 500 feet in elevation change. Trails are nicely graded. Trailhead elevation is around 640 feet, and the high spot is around 1100 feet.

Mix of shade and sun.

Trail traffic:

Trail surfaces:
Dirt trails and fire road.

Hiking time:
1 1/2hours.

Nice any time.

Getting there:
From Interstate 280 in San Mateo County, exit Alpine Road. Drive southwest on Alpine Road about 3.6 miles (past the junction with Portola Road), to a small roadside pullout on the right side of the road, just before Willowbrook Drive.

Get driving or public transit directions from Transit and Trails:

GPS Coordinates* for Trailhead:
Latitude 3721'51.81"N
(* based on Google Earth data, shown as degrees, minutes, seconds)

Gas, food, and lodging:
Gas, pay phone, and store back near the junction with Portola; more services back to the northeast near 280.

Trailhead details:
Parking for a few cars in the pullout, and room for a few more on the side of Willowbrook. Mind the no parking signs. If there's nowhere to park near the trailhead, you can park on the side of Alpine near the junction with Corte Madera, about 0.4 mile back to the northeast. Then walk into Coal Mine Ridge on Alpine Trail. No parking or entrance fees. No restrooms or drinking water. No designated handicapped parking, and trails are not suitable for wheelchairs. Maps sometimes available at the trail entrance. Refer to the Portola Valley's trail map for details. There is no direct public transportation to the park, but SamTrans bus #282 stops in nearby Portola Valley.

No bikes. Dogs are permitted on leash on some trails (but not the trails described in the hike featured on this page). One trail is designated hiking only, while others are open to equestrians and hikers.

The Official Story:
Portola Valley's Coal Mine Ridge page (pdf)
Portola Valley Town Hall 650-851-1700

Map Choices:
• Use AAA's San Francisco Bay Region map to get there.
Map from Portola Valley (pdf -- the town seems to have renamed the park Portola Valley Ranch)
Trail Map of the Southern Peninsula, by the Trail Center (order this map from
Peninsula Trails, by Jean Rusmore, has a simple map and trail descriptions (order this book from
The Santa Cruz Mountains Trail Book, by Tom Taber, has a simple map (order this book from

View photos from this hike

Go to Bay Area Hiker Home page

The small town of Portola Valley, nestled in the valley foothills of the Santa Cruz Mountains, maintains an unusual commitment to non-automotive transportation options. Side of street parking along Alpine Road Pedestrian path parallel main thoroughfares around town, and a few trails take scenic routes through less populated areas. Coal Mine Ridge is owned by the Portola Ranch Homeowner's Association, and while the land is private property, trail use is permitted by town easement. Please remember to respect the property rights of the generous land owners who share their "park" with us, and do not wander off trail. Volunteers maintain this roughly oval parcel of land, with four main trails that create a series of loops through woods and oak grassland. There are no facilities, and parking can be tough. However, it's well worth overcoming any of these obstacles, for Coal Mine Ridge is one of the best places to hike on the peninsula.Toyon Trail
     This isn't a preserve that shines only in one season. A mixed woodland harbors flowers in spring, and provides shade through the sultry days of summer. Paths are littered with fallen maple and black oak leaves in autumn. Winter rains wake up tiny dormant streams and return the green to grassland. If you like to study bay area plants, you'll find a lot to look at here, all year round.
      Start at the broad pullout on Alpine Road. Walk toward Willowbrook Drive and carefully cross the street. Alpine Trail, open to hikers and equestrians only, starts at the signed trailhead and climbs easily under the shade of California bay, buckeye, madrone, and black oak. In the understory look for currant, thimbleberry, blackberry, snowberry, and poison oak.At about 0.1 mile, Alpine Trail steps out of the shade and meets Toyon Trail at a signed junction. Turn right onto Toyon Trail.View west to Windy Hill
      The narrow hiking-only trail heads back into the woods. In addition to previously encountered California bay, buckeye, madrone, and black oak, coast live oaks are common, and you also might see big leaf maple (most conspicuous in autumn). Other trailside plants include gooseberry, honeysuckle, wood rose, clematis, ceanothus, California coffeeberry, and creambush. Hazelnut is abundant; look for the nuts in early summer. Late winter flowers include milkmaids, hound's tongue, and trilliums. Toyon Trail angles along the hillside at a mostly level pace, with a somewhat steep drop-off to the right permitting some sweeping views west where there are breaks in vegetation. The grassy slopes of Windy Hill are prominent, bordered to the north and south with forests of Douglas fir. Squeezing through some madrones Although Alpine Road is not visible, there is some attendant noise from the street and nearby houses. Rough benches, placed in intervals along the trail, provide nice places for a rest break. A rustic bridge replete with a rope handrail crosses a seasonal creek. Soon after, at about 1 mile, Toyon Trail reaches a signed junction with a trail connecting to Coal Mine Trail. Continue straight on Toyon Trail.
     The trail passes through a few open spots where you might see chamise, sagebrush, coyote brush, toyon, and monkeyflower. Shooting stars and saxifrage are conspicuous in early March, and by mid to late spring, trailside buckeyes put forth sweet-smelling blossoms. Coast live oaks tower over the trail, accompanied by madrones and a few young Douglas fir. At about 1.9 miles, you'll reach a signed junction. Turn left, "to Old Spanish Trail."Old Spanish Trail
     The narrow path climbs slightly, past some cercocarpus, then squeezes through a few madrones and ducks under an old coast live oak. At about 2 miles, you'll reach a signed, multi-trail junction. The first trail clockwise to the left is Coal Mine Trail, the second and third are arms of Old Spanish Trail (the fourth trail loops around and then rejoins the junction). Continue straight on Old Spanish Trail.
     The broad trail, open to hikers and equestrians, starts a gentle descent (you might not realize that well-graded Toyon Trail gains over 300 feet in elevation). Views to the east unfold on the right side of the trail, which is lined with coyote brush, coast live oak, ceanothus, and toyon. Bright pink clarkia is a cheerful sight, blooming in late spring and early summer. Look for an out-of-place knobcone pine on the left, an anomaly in the valley oak-dotted grassland. At about 2.4 miles, Old Spanish Trail crosses a gravel service road, then reaches a signed junction. Coal Mine Trail departs to the left, heading back uphill. Turn right and remain on Old Spanish Trail.Old Spanish Trail
     The trail briefly descends along the service road, then reaches another signed junction at about 2.5 miles. Bear left on Old Spanish Trail. California bay and coast live oak shelter the trail as it winds gently downhill, passing a few black oak. Stepping out into coyote brush and oak grassland, you probably will get a sense of your proximity to the trailhead, as noise from Alpine Road may be audible. At about 3 miles, Old Spanish Trail ends at a signed junction with Alpine Trail. Turn left, and almost immediately, you'll reach the previously encountered junction with Toyon Trail. Continue straight and retrace your steps back to the trailhead.

Total mileage: about 3.1 miles
Last hiked: Tuesday, February 24, 2004