Camino Alto Open Space Preserve,
Marin County Open Space District,
Marin County
In brief:
2.7 mile partial loop through open space bordering Mill Valley neighborhood, includes a short distance on steep paved streets.

Distance, category, and difficulty:
This 2.7 mile partial loop hike is easy. Trailhead elevation is around 360 feet. The featured hike starts out level, climbs steeply to about 730 feet, descends moderately steeply, then returns to the trailhead on a level trail: total elevation change is about 500 feet.

Mostly exposed.

Trail traffic

Trail surfaces
Dirt fire roads and one paved street.

Hiking time
Less than 2 hours.

Hot in summer, otherwise nice any time.

Getting there:
From US 101 in Marin County, exit East Blithedale/Tiburon Boulevard. Drive west on East Blithedale about 0.8 mile, then turn right onto Camino Alto. Drive north on Camino Alto about 0.5 mile, then turn left onto Overhill. Drive uphill about 0.2 mile on Overhill, then turn right onto Escalon. Park on the side of the road.

Get driving or public transit directions from Transit and Trails:

GPS coordinates* for trailhead:
Latitude 3754'35.22"N
(* based on Google Earth data, shown as degrees, minutes, seconds)

Gas, food, and lodging:
Gas, pay phones, stores, and restaurants back around Camino Alto and East Blithedale in Mill Valley. No camping.

Trailhead details:
Side of street parking at the edge of a residential neighborhood. There are no parking or entrance fees. No drinking water, maps, or restrooms. No designated handicapped parking, but if trail conditions are agreeable wheelchairs users may be able to navigate some distance on Escalon Fire Road. There is no direct public transportation to this trailhead. You could pedal from the bus stop on East Blithedale in Mill Valley, but it's not a safe walk on Camino Alto to the trailhead. Note: Camino Alto's trail names vary in maps and trail books, and none of the trails are signed.

Trails are multi-use. Dogs permitted on the hike described below: they are allowed on leash on trails and fire roads, or under voice command on fire roads only.

The Official Story:
MCOSD's Camino Alto page
MCOSD 415-499-6387

Map Choices/More Information:
• Use AAA's San Francisco Bay Region map to get there.
• Download the pdf map from the MCOSD website.
• Trails of Mt. Tamalpais and the Marin Headlands, by Gerald Olmsted (order this map from is useful.
Mount Tam Trail Map, published by Tom Harrison Maps (order from Tom Harrison Maps). Comparable to the Olmsted map.
• Open Spaces:  Lands of the Marin County Open Space District, by Barry Spitz (order this book from has a simple map and detailed trail descriptions.
• Hiking Marin by Don and Kay Martin (order this book from has a useful map and a suggested hike through Camino Alto.

View photos from this hike.

Go to Bay Area Hiker Home page

Camino Alto, comprised of a few fire roads wrapped around developed areas in the lower southeast foothills of Mount Tam, is an ideal neighborhood preserve. Trailhead At the Escalon trailhead, less than a mile from the busy intersection of East Blithedale and Camino Alto (the road), parking is ample, permitting easy access. Dogs are allowed on the preserve's trails, and you'll likely see walkers greeting each other (and their canines) by name. Although folks and their dogs who live nearby get the most use out of the preserve, Camino Alto makes a fine staging area for long Tam hikes, or short walks or jogs. Escalon and Upper Summit Fire Roads are nearly flat, while Middle Summit Fire Road is moderately steep. You can take an out-and-back hike on either, or bridge the two routes together with a short (but steep) walk on paved Summit Road. Escalon Fire RoadFor a long out-and-back hike with plenty of elevation change, start on Escalon Fire Road, then string together Middle Summit Fire Road, Corte Madera Ridge Fire Road, and Blithedale Ridge Fire Road. Turn back wherever you choose -- there are dynamite views of Mount Tam and the surrounding area along most of the route.
      For the featured hike, start at the open space gate at the end of Escalon Drive. Broad, multi-use Escalon Fire Road weaves at an even pace through coast live oak, California bay, toyon, madrone, coyote brush, monkeyflower, a few redwood, and plenty of invasive broom. Trees block most views, but look for a clear spot on the right where you might have a view south to San Francisco, and east to Horse Hill (part of the Alto Bowl Open Space Preserve) and Ring Mountain. Upper Summit Fire RoadUS 101, blocked by Horse Hill, is not visible. Traffic and neighborhood noise are common as the fire road runs north between Camino Alto (the road) and housing developments, some still under construction. At 0.12 mile you'll reach an unsigned junction with Camino Alto Fire Road. Continue straight.
     Escalon Fire Road continues at a level grade, skirting a hill on the right. Redwoods and hazelnut thrive in some sections, while coast live oak, madrone, and California bay remain common. In summer, long after most wildflowers have bloomed, you might see pink clusters of buckwheat and purple coyote mint along the trail in dry areas. On a clear day there's a lovely view of Mount Tam on the left. At 0.65 mile you'll reach an unsigned multiple junction (in Tamalpais Trails Barry Spitz reports MCOSD rangers calls this interchange the "Escalon Octopus"). Summit RoadMiddle Summit Fire Road crosses the fire road, which according to the MCOSD map becomes Upper Summit Fire Road here (even though it attains a lower elevation than Middle Summit Fire Road). Continue straight, to the left of the pumphouse, on Upper Summit Fire Road.
     The name may have changed, but the trail remains the same, a wide nearly-level fire road open to hikers, equestrians, and cyclists. As Upper Summit Fire Road edges around a hillside, to the left, redwoods and California bay make the most of the hill's shelter. You may notice coast live oak, buckeye, and thimbleberry, and more broom in the sunnier stretches of trail. At 1.29 miles Upper Summit Fire Road ends at an open space gate, at the edge of a residential neighborhood. Continue straight to an unsigned junction with paved Summit Road at 1.30 miles, then turn left.Middle Summit Fire Road
     This narrow road, accessing houses and estates, climbs sharply. Watch out for vehicles. The grade is relentless, but you may occupy yourself looking for tiny-leaved yerba buena growing on the sloping hillsides along the road. At 1.54 miles Summit Road makes a tight turn right, continuing uphill. Look for an open space gate straight ahead, to the left of a water hydrant.
     Once on the other side of the gate, you'll begin walking downhill, on Middle Summit Fire Road. Be sure to pause for a look east, over the bay and all the way to the hills of Contra Costa County. Another wide, multi-use fire road, Middle Summit Fire Road almost immediately adopts a moderately steep downhill grade. Coast live oaks are the dominant trailside plant, although you might also see madrone, California bay, and broom. View to Tam from Middle Summit Fire Road A few small rock rose plants, with bright pink flowers, are conspicuous in late spring and early summer. The descent is broken up by a single short steep hill. Through the trees and downhill to the left you might be able to make out patches of Upper Summit Fire Road. At the top of the hill, before the trail descends again, there's a lovely view of Tam, to the right. The fire road presses on downhill, giving up more nice views east along the way. Several spacious houses are visible on the right; the fire road runs along the preserve boundary here. At 2.02 miles you'll return to the Escalon Octopus. Turn right and retrace your steps back to the trailhead.

Total distance: 2.66 miles
Last hiked: Monday, July 22, 2002