Summit Loop,
San Bruno Mountain State and County Park,
County of San Mateo Parks, San Mateo County
In brief:
3.5 mile loop to the summit, with loads of native vegetation all along the trails.

Distance, category, and difficulty:
This 3.5 mile loop hike is easy, with about 650 feet in elevation change. Trailhead elevation is around 730 feet. Highest elevation on this hike is around 1200 feet. The hikes climbs and descends on well-graded, but rocky trails. This is a good hike for beginners.

Mostly exposed.

Trail traffic:

Trail surfaces:
Dirt trails.

Hiking time:
2 hours.

Nice any time, but best in spring.

Getting there:
• From southbound US 101 in San Francisco County, exit #429B Cow Palace/Third Street. Drive south on Bayshore about 2 miles, turn right on Guadalupe Canyon Parkway and drive uphill about 2 miles to the park entrance on the right side of the road.
• From northbound US 101, take Exit 426A toward the Cow Palace and drive north on Bayshore Boulevard; then turn left onto Guadalupe Canyon Parkway.
• From Interstate 280 in San Mateo County, exit #50 Mission Street, then take Market to Guadalupe Canyon Parkway and drive east to the park entrance on the left side of the road (it's about 3 miles from 280).

Get driving or public transit directions from Transit and Trails:

GPS Coordinates* for Trailhead:
Latitude 3741'42.63"N
(* based on Google Earth data, shown as degrees, minutes, seconds)

Gas, food, and lodging:
Gas, restaurants, and stores available to the northeast on Bayshore near Geneva, and to the west near I-280. No camping.

Trailhead details:
$6 entrance fee (self-registration if kiosk is unstaffed). Maps available at the kiosk. Once past the kiosk, drive past the first lot, under the parkway to the trailhead on the south side of Guadalupe Canyon Parkway. Parking for about 20 cars. Restroom and pay phone available near the trailhead on the north side of Guadalupe Canyon Parkway. One designated handicapped parking spot, and trails may be wheelchair accessible with assistance. There is no direct public transportation to the park.

Bikes permitted on a few trails. Horses and hikers share the rest. No dogs. Park is open from 8 a.m. to 8 p.m. (may close earlier in winter).

The Official Story
CSMP's San Bruno page
Park office 650-992-6770

Map Choices/More Info:
This hike is described and mapped in 60 Hikes within 60 Miles: San Francisco, by Jane Huber (yup, that's me, the creator of this website). Order this book from
Map from CSMP
Afoot and Afield: San Francisco Bay Area, by David Weintraub (order this book from has a great map and descriptions of this hike.
Trails of the Coastside and Northern Peninsula (map) is a good guide (available from Pease Press).
Peninsula Trails, by Jean Rusmore, has a simple map and trail descriptions (order this book from
• Tim Taber's The Santa Cruz Mountain Trail Book has a simple map and park descriptions (order this book from
Bay Nature article about San Bruno Mountain

View 79 photos from the featured hike.

Go to Bay Area Hiker Home page

The third time proved to be the charm for me at San Bruno Mountain Park. Photo of trailheadOn my two previous visits I tried the Ridge Trail, and Saddle Trail. The parking area near the summit, which serves as the trailhead for the Ridge Trail, is used as a party spot by locals on occasion, and I felt uncomfortable hiking alone there. Saddle Trail is heavily used by joggers (also open to cyclists), and is a short, kind of bland loop. But like Goldilocks, I found the third hike was just right. Summit Loop Trail climbs easily on a well-graded path to the ridge line, and then drops back to the trailhead, about a 3.5 -mile circuit. Along the way, the trail runs along a creek, ascends through chaparral, and provides excellent views of downtown San Francisco, the East Bay hills, and the Santa Cruz Mountains from the ridge. The spring wildflowers are outstanding; lots of variety and something blooming just about everywhere. I have a soft spot in my heart for San Bruno Mountain, because it was here I first saw a coyote (along the side of Radio Road).Photo of Summit Loop Trail
     There are 4 loops of various lengths at San Bruno. The most popular seems to be Saddle Trail, which is a nearly flat 3 mile circuit originating at the trailhead on the northern part of San Bruno (close to the entry kiosk). Of the trails south of Guadalupe Canyon Parkway, Summit is the longest and most challenging loop, though still an easy 3.1 mile hike. Eucalyptus Loop Trail is just over 1 mile, and Dairy Ravine Trail and Summit Loop can extend that loop another 1/2 mile or so. Ridge Trail is an out and back path (2.4 miles one way), the only trail in the southern portion of the park. To access Ridge Trail, park at the summit lot, at the end of Radio Road.
     For the featured hike, start at the trailhead near the volunteer-built demonstration garden. Follow the signpost's directions toward the Summit Loop Trail, right (west). Photo of Summit Loop TrailThe path splits into the two ends of Summit Loop Trail after just 350 feet. Bear right at the signed junction.
      Shortly after, the trail crosses the street. This narrow path, closed to cyclists but open to equestrians, descends slightly through grassland, with elderberry trees giving way to eucalyptus and cypress trees as Summit Loop Trail nears a creek. In the spring, expect to see suncups and blue-eyed grass. After a damp fern-lined stretch, the path turns west and runs parallel to Guadalupe Canyon Parkway, which is visible and audible, but not much more than a passing distraction from the flowering cow parsnip, blackberry vines, sticky monkeyflower, California poppies, scarlet pimpernel, strawberry, California buttercup, and checker-bloom. A tiny bridge crosses a damp spot where shrubs have grown up and over the trail like an arbor. Summit Loop Trail makes a turn to the south and runs along April Brook. You might see lupine, manroot, and bluedicks blooming in the spring,and California scorpionweed, which has a distinctive curving flower bract, and dusky purple flowers. Coyote brush, lizardtail, California coffeeberry and ferns line the trail. View back to the north After crossing April Brook, Summit Loop Trail turns north and begins a gentle climb. California sagebrush becomes a dominant plant, but showy springtime plants include poppies, checker-bloom, and an occasional johnny-jump-up. Traffic noises recede as the trail ascends. Hummingbirds, hawks, northern harriers, and vultures swoop through the skies, along with a variety of butterflies, including red admirals and common buckeyes. A bench provides a nice spot to look back downhill, gauging the progress you've made. Mount Tamalpais pops up to the north, and San Bruno Mountain's summit is visible to the south. Summit Loop Trail continues an easy climb through the shrubby plants. A sharp-eyed hiker may pick out the distinctive holly-shaped leaves of Oregon grape, and the aptly named twinberry bush. Closer to the ground, goldenfields provide a burst of yellow color in the spring. Poison oak thrives in large clumps along the trail. Summit Loop Trail Fences keep trail users away from communications equipment on the ridgeline, as the path continues to climb toward the summit. Figwort, cinquefoil, and nightshade may be glimpsed along the path, as cottontail rabbits and lizards scurry through the scrub. A special treat in spring is the emergence of hummingbird sage's large purple flowers. At 2 miles, Summit Loop Trail crosses a private, gated road and makes a run for the ridgeline. Views to the west are unobstructed, and include Montara Mountain, the Farallones, and the ocean. It can get very windy up here, and only sturdy plants thrive, but look for bush lupine, poppies, owl's clover, and plenty of irises in the spring. Some shortcuts have been worn in, making it tough to pick out the official trail. At 2.36 miles, Summit Loop Trail crosses the road again (for the last time!), at the hike's high spot, then begins a drop to the east. The views to the east and north distract from the trail. At a signed junction at 2.44 miles, Ridge Trail heads south on the right side of the trail. Continue straight on Summit Loop Trail.Photo of view north, with patches of gorse visible
      Ceanothus is common along the trail, as are more blooming flowers in the spring, particularly paintbrush, goldenfields, and poppies. You might even notice a few huckleberry shrubs. A bench sits on the edge of a bluff and features million dollar views of downtown San Francisco, Marin, and the East Bay, including Mount Diablo. A few steps later Dairy Ravine Trail begins on the right side of the trail at a signed junction, at 2.61 miles. Either Summit Loop or Dairy Ravine are optional here; for the featured hike, turn right on Dairy Ravine Trail.
     Dairy Ravine Trail switchbacks gently downhill, through a panoply of springtime flowers, including johnny-jump-ups, poppy, bluedicks, goldenfields, California buttercup, scorpionweed, blue-eyed grass, rock cress, checker-bloom, and paintbrush.This side of the mountain is frequently visited, and so shortcuts are common. The trail approaches a grove of eucalyptus trees growing in Dairy Ravine, but turns back into grassland, away from the ravine. Photo of Dairy Ravine TrailThis eastern exposure is more dry and exposed than the northern exposure Summit Loop Trail passed through earlier, so moisture-loving plants like cow parsnip are few and far between. Dairy Ravine Trail ends at a signed junction with Eucalyptus Loop Trail at 3.04 miles. Again, either end of the trail returns to the trailhead, but for the featured hike, turn right.
     As Eucalyptus Loop Trail winds downhill, the path features views to the remote southern canyons and slopes of the mountain. A faint, unsigned trail breaks off on the right side of the trail. This is Old Ranch Road, which runs a ways along Guadalupe Canyon Parkway and then ends. Continue straight on Eucalyptus Trail. The trailhead is visible straight ahead. Eucalyptus Trail ends just before the parking area.

Total distance: 3.54 miles
Last hiked: Saturday, April 3, 2004