The Trail Companion

December 1996/January 1997

Faults, Volcanoes and Hawks: Exploring the Ridges with the new Trail Map of the Southern Peninsula

by Geoffrey Skinner

Take a hike, a canter or a spin this month with our new Trail Map of the Southern Peninsula! This month's exploration will give you sweeping views of the bay and ocean, take you through four Midpeninsula Regional Open Space District (MROSD) preserves, along the Bay Area Ridge Trail and across two major faults. The roughly 6-mile route, mostly through open grasslands, is particularly suitable for the cooler months.

Take Skyline Boulevard (Highway 35) or Page Mill Road to the intersection of Alpine Road and Skyline Boulevard. The Russian Ridge Open Space Preserve parking is off Alpine Road immediately to the west of the intersection. From the parking lot, take the Ridge Trail up the hill to the north. Once you reach the ridge top, continue climbing until you come to the intersection with the connector trail leading to the Ancient Oaks trail (0.7 mi.). Watch for rough-legged hawks flying overhead and take time to climb Borel Hill (2572 ft.) to the east or the unnamed hill to the southwest (2571 ft.). As you enjoy the 360-degree panorama, look west for a view of the slightly lower Mindego Hill. The hill is part of the Mindego Volcanics, a formation that resulted from an ancient submarine volcano located in shallow seas near the present-day La Honda before the Santa Cruz Mountains were pushed skyward. Mindego Hill itself is beyond the preserve boundary although you can follow trails nearly to Mindego Hill's base.

Continue past Borel Hill on the Ridge Trail, descend to the intersection with Mindego Ridge Trail (0.3 mi.). The Ridge Trail continues north with a short jog to the west; go east to Skyline Boulevard and cross to the CalTrans vista point on the other side (an alternative starting point for this loop). Walk north on Skyline Boulevard approximately to the first road on the right (0.1 mi.). Following this road, you will reach a gate and see a sign for Coal Creek Preserve. Enter the preserve and continue on the road to an intersection at the edge of the woods (0.4 mi.). The route follows the road to the right toward the southern end of the preserve, but the ridge directly below the intersection is worth exploring, particularly in spring, when an abundance of wildflowers bursts out on the rocky slopes.

The open ridge is also noteworthy for the view across the Corte Madera Creek canyon below to the next ridge, Coal Mine Ridge. The ridge is a thin sliver of a sedimentary formation commonly found in the Santa Clara Valley that has been caught between two large faults and squeezed upward. Corte Madera Creek flows along the path of the Pilarcitos fault (an ancient trace of the San Andreas Fault before the rift moved east to its present location) and Los Trancos Creek occupies the rift zone of the San Andreas fault. If you look north, you can easily spot the San Andreas Rift Zone as it passes through Woodside and Crystal Springs Reservoir. The Pilarcitos fault follows the main ridge of the Santa Cruz Mountains north until plunging into the Pacific just north of Montara Mountain.

The trail descends gently through oak woods before dropping through open country again and meeting Alpine Road (0.6 mi.). This 2.3-mile section of Alpine has been closed to motor traffic since the mid-70s, but remains open to hikers, horses, and bicyclists. Winter rains in 1995 and 1996 caused a large slide which forces trail users onto narrow and steep informal trails; San Mateo County is currently debating the future of the section and is looking at options including closing the section altogether, as well as paving it to provide emergency access for the future.

Take Alpine Road uphill to the south (hikers should be cautioned that Alpine Road is a favorite with cyclists, often traveling at high speeds) until you reach Page Mill Road (0.5 mi.); cross the road and enter the gate to Monte Bello preserve. A trail travels straight ahead and downhill , but it dead-ends after a short distance; take instead the trail veering left up the ridge to the parking area signed as "By permit only" and continue to the Weeping Oaks Trail intersection (0.3 mi.). (The main Montebello parking is one of the alternate starting points for this route: a 0.3 mi. trail takes you from near the restroom to the Weeping Oaks Trail intersection).

Descend the open ridge on the Weeping Oaks Trail toward the Skid Road Trail (1.2 mi.), but before you reach the oak forest, notice Stevens Canyon directly to the south, flanked by Monte Bello Ridge to the east and Skyline Ridge to the west. The entire canyon is part of the San Andreas Rift Zone and at this point you are standing between the Pilarcitos and San Andreas faults. Incidentally, the portions of the San Andreas visible on this hike all belong to the segment thought most likely to cause the next major quake on the San Andreas fault in the Bay Area.

Walk through the oak-filled canyon until you reach Skid Road Trail. The Stevens Creek Nature Trail, only a short distance down to the left, makes a very pleasant 3 mile addition to our route if you want to extend your hike; otherwise, go up the hill on the Skid Road Trail to meet Skyline Boulevard again (0.3 mi.). Cross the stile on the other side and enter Skyline Ridge Preserve, the fourth on this loop. Head through the parking lot on the right (yet another possible starting point) and begin the ascent on the second segment of the Ridge Trail as it goes north to Russian Ridge.

This section of the Ridge Trail climbs through magnificent oaks until it emerges into grasslands and intersects with the alternate Ridge Trail route (0.5 mi.). (Bicyclists must use the alternate route, which runs from the Skyline parking lot past Horseshoe Lake and climbs to the top of Skyline Ridge before dropping to Alpine Pond. The rest of the loop described in this article is open to all trail users.) Go straight at this intersection, entering the chaparral as you swing to the north. Despite the brush, the trail offers great views of Big Basin, and on a clear day, the Santa Lucia Mountains to the south beyond Monterey. If you look down the hillside, you may also get a glimpse of the old Page Mill Road as it drops toward the Page Mill site in Portola State Park several miles away.

Continue north until you enter oak forest again and descend to Alpine Pond (0.9 mi.). Notice the beautiful trails, the David Daniels Nature Center, and the many small willows--MROSD has made efforts in developing and restoring this part of the preserve to make it accessible to all. You can now return to the Russian Ridge parking lot by either the Ridge Trail tunnel under Alpine Road on the east side of the pond or the alternate Ridge Trail route from the dam to the west (bicyclists and horses must take the alternate route) (0.2 mi.), but if you have time, relax by the pond, pull out your Southern Peninsula map and look at the many other wonderful trails begging for your next outing!

(Note: An earlier version of this route appeared in the Dec. 1990/Jan. 1991 issue of the Trail Companion)