King Mountain Open Space Preserve,
Marin County Open Space District,
Marin County
In brief:
3.3 mile partial loop around King Mountain, above a Larkspur neighborhood.

Distance, category, and difficulty:
There are a couple short steep portions of fire road, but this is an easy 3.3 mile semi-loop hike, with about 500 feet in elevation change. Trailhead elevation is about 70 feet. The preserve's highest (public) point is about 650 feet.

Mixture of sun and shade.

Trail traffic

Trail surfaces
Dirt fire roads and trails.

Hiking time
1 1/2 hours.

Good anytime.

Getting there:
From US 101 in Marin County, exit Paradise/Tamalpais Drive. Drive west on Tamalpais about 0.8 mile, then turn right at the stop sign onto Corte Madera. Drive about 1 mile (Corte Madera becomes Magnolia), then turn left at the traffic light onto Ward. Drive about 0.1 mile on Ward, then turn right onto Hawthorne. Almost immediately, turn left onto Willow. Drive less than 0.1 mile, then look for parking near the fire road on the right.

Get driving or public transit directions from Transit and Trails:

GPS coordinates* for trailhead:
Latitude 3756'14.27"N
(* based on Google Earth data, shown as degrees, minutes, seconds)

Gas, food, and lodging:
Pay phone, gas, stores, and restaurants in downtown Larkspur, or back in Corte Madera. No camping.

Trailhead details:
Side of the road parking in a residential neighborhood. Note that parking is only permitted in the white-outlined spaces. No parking or entrance fees. No drinking water, restrooms, or maps. No designated handicapped parking, and trails are not suitable to wheelchairs. There is no direct public transit to the preserve, but Golden Gate Transit buses run along Corte Madera Avenue, and you could easily walk to the trailhead.

The fire road is multi-use, but King Mountain Loop Trail is signed closed to cyclists. Dogs are permitted on leash on trails; off leash under voice command on fire roads. Dog owners must have a leash for each dog.

The Official Story:
MCOSD's King Mountain page
MCOSD 415-499-6387

Map Choices:
• Download the Baltimore Canyon/Blithedale Summit pdf map from the MCOSD website.
• 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.
• 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.
• Hiking Marin by Don and Kay Martin (order this book from features a good map and descriptions of this hike.

View photos from this hike.

Go to Bay Area Hiker Home page

King Mountain Open Space Preserve seems nothing short of miraculous. Beautiful King Mountain, just a stone's throw from downtown Larkspur, is blessed with easy access and fantastic views. TrailheadThe preserve could easily have become (for example) Ye Olde King Mountain Luxury Estates. As it is, the very top of the mountain is privately held, but MCOSD owns the lower reaches, and a loop trail bisects the private property thanks to an easement.
     Visitors head into the preserve from fire roads at the edge of residential Larkspur, a few short blocks from downtown. A single fire road climbs to King Mountain Loop Trail, which makes a 1.8 mile circuit of the mountain. Although this hike is short, the trail is fantastic and there's plenty to see along the way. If you want to extend this hike, you could add on an out-and-back excursion to Dawn Falls via Ladybug Trail, which connects King Mountain to Baltimore Canyon Open Space Preserve. Longer hikes into the heart of Tam are possible, but you'll face substantial elevation changes as you climb and then descend from ridge to ridge.Citron Fire Road
     A variety of plants thrive on the flanks of King Mountain, and trails travel through shaded mixed woodland, sunny patches of grassland and chaparral, and redwood, tanoak, and California bay canyons. All the land (except the redwood canyons) is sporadically infested with french broom, an invasive non-native shrub that grows fast and prevents native plants from taking root. Other foreigners acacia and eucalyptus are confined to low elevations on the eastern part of the mountain. The best possible time I can imagine for a visit is a spring day after a rainstorm. The woods and grassland will be dotted with wildflowers and you'll see tiny waterfalls in the mountain's creases. The other seasons pale by comparison, but King Mountain is pretty year round.Woods on King Mountain Loop Trail
      Start at the fire road on Willow, unnamed but marked by red and blue "fire road" signs. The wide multi-use trail climbs easily through coast live oak, California bay, poison oak, and cotoneaster. After only about 450 feet, you'll reach a broad dirt circle (the end of Cedar Avenue) and open space gate. (You can also park in this area, but don't block the gate, and beware of mud in winter.) There's a small creekbed downhill to the left, and a sloping hillside ascends straight ahead towards the top of King Mountain. Here on the lower reaches of the mountain, non-natives eucalyptus, broom, and acacia, with free reign for years, have established themselves as the dominant plants. You might notice piles of uprooted broom and acacia along the trail, but there are still lots and lots of young acacia seedlings, and broom keeps reestablishing itself. Ironically, the native plant with the most real estate seems to be poison oak, but there are a few oaks and some coyote brush along the trail. As you climb a few paths head left toward surrounding neighborhoods, but stay on the wide trail. A view of Tam from King Mountain Loop TrailCitron Fire Road (also known as Cedar Fire Road) curves left and crosses the creek, then ascends sharply. After a short climb, the trail curves right and levels out. Already there are sweeping views east, to Mount Diablo, the bay, and San Quentin. A few toyon shrubs break the monotony of poison oak, coyote brush, and broom. The trail will likely be muddy during the wettest months of the year. At 0.52 mile, there's an unsigned junction with another fire road bending right. Continue left/straight on Citron Fire Road.
     The trail descends slightly, then draws near and curves left past a white gate and paved road. There are views, west to the summit of Tam, and north to Big Rock Ridge. Another short but steep ascent follows, and an assortment of trees creep toward the trail on the right. At 0.73 mile, you'll reach a signed junction with King Mountain Loop Trail. Citron Fire Road continues straight, ending a short distance uphill. Turn left onto King Mountain Loop Trail.Waterfall on King Mountain Loop Trail
      The narrow hiking and equestrian trail winds a few steps through coast live oak and California bay. Look for one particularly massive and beautiful coast live oak on the left. As King Mountain Loop Trail emerges into a patch of grassland, look left for a long view east. Traffic sounds are quite clear, but the trail steps into the woods, blocking all views for now. The trail contours across the mountain at an almost level pace. Coast live oak, madrone, and California bay are dominant, but you might also see a variety of ferns in the shade, and monkeyflower, poison oak and broom in sunny spots. In mid-winter look for milkmaids and hound's tongue in bloom. Buckeyes cluster together along shady creekbeds, where after a substantial winter storm, tiny waterfalls cascade downhill. There's one waterfall in a pocket of grassland that was so pretty I had to sit down at the edge of the muddy trail and enjoy the soothing sound of running water for a few minutes. King Mountain Loop Trail Although it was early February, I noticed thousands of wildflowers poking up from the grass; this must be a stunning destination in spring. Continuing on the trail, there's so much to enjoy that you might forget to savor the occasional views to Mount Tam. Traveling west noises fade, and the only sounds I heard were birds chirping, water trickling, and leaves rustling. A clump of hazelnut shrubs grace the trail on the left. At 1.55 miles, you'll reach an undersigned junction with a trail connecting left to Wilson Way. Continue straight and remain on King Mountain Loop Trail.
     The trail elevation fluctuates mildly, and the hiking remains easy. You might hear hawks shrieking in the skies overhead, but tree cover blocks most views. Every once in awhile there's a break in vegetation to the left, and you'll have another Tam vista. At 1.63 miles you'll reach a signed junction with Ladybug Trail (also shown on some maps as Contractors Trail). Ladybug departs downhill into Baltimore Canyon Open Space Preserve; if you want to visit Dawn Falls, turn left here and then right onto Dawn Falls Trail. Otherwise, bear right to remain on King Mountain Loop Trail.Descending through redwood and tanoak
      Ascending a bit, the trail passes a few huckleberry bushes on the left. Madrones are very common on the sides of the trail. A simple wooden plank bridge keeps the trail level at a creek crossing. King Mountain Loop Trail steps out into a sunny stretch of chaparral, where toyon, pitcher sage, chamise, and coyote brush frame another nice view west. The trail grade stiffens noticeably, and the trail, here rutted and eroded, shoots uphill and ducks under a sprawling coast live oak. A path continues steeply straight uphill, but an easier re-route veers right. There are a few California coffeeberry shrubs and young tanoaks along the trail. Just past a line of manzanita shrubs, you'll reach an undersigned junction at 2.03 miles. Ridgecrest Road descends to the left. Turn right.
    Walk uphill a few feet, passing the gated private property to the right, then veer left. A generic MCOSD trail sign on the right marks the continuation of the trail. Returning down Citron Fire Road The descent, through redwood, tanoak, and California bay, is easy thanks to a series of well-made and attractive wooden steps. As the trail switchbacks left, you might notice a few clumps of pampas grass, yet another invasive non-native plant. King Mountain Loop Trail crosses a creek on a bridge, where a rustic bench sits in the depths of this canyon. Leveling out, the trail passes a handful of California nutmeg trees. A few more seasonal creeks cascade downhill in winter through here. Some pretty California bays have grown into an arch across the trail. The tree cover screens all views, but sounds from civilization herald a return to the eastern slopes of the mountain. At 2.56 miles, you'll reach a previously encountered junction with Citron Fire Road. Turn left and retrace your steps back to the trailhead.

Total distance: 3.29 miles
Last hiked: Friday, February 8, 2002