Sugarloaf Ridge State Park,
California State Parks,
Sonoma County
In brief:
This hike starts at the edge of a sloping meadow and climbs steadily through a mixture of grassland, chaparral, and mixed woodland for 2.5 miles to the summit. The return route travels along a quiet ridge, drops steeply through gray pines and chaparral to cross Sonoma Creek twice, then wanders through a meadow on the way back to the trailhead.

Distance, category, and difficulty:
6.2 mile loop hike is moderate.

Mostly exposed.

Trail traffic

Trail surfaces
Dirt trails and fire roads, and one paved segment.

Hiking time
3 hours.

Nice any time, but best in early spring.

Getting there:
From US 101 in Sonoma County exit #488b onto CA 12. Drive east on CA 12 toward Sonoma for 1.5 miles, then turn left on Farmer's Lane. After about 1 mile, turn right onto Fourth Street/CA 12, drive southeast about 8 miles, and turn left onto Adobe Canyon Road. Drive east 3 miles to the entrance kiosk, pay the fee, and then continue a short distance to the parking lot on the left.

Get driving or public transit directions from Transit and Trails:

GPS coordinates* for trailhead:
Latitude 3826'16.79"N
(* based on Google Earth data, shown as degrees, minutes, seconds)

Gas, food, and lodging:
Available in and around Santa Rosa. Sugarloaf has a campground.

Trailhead details:
Pay $8 day use fee at the entrance kiosk. The park map is available at the visitor center or entrance kiosk (when staffed). Portable toilet located at the trailhead.

Dogs are not permitted on park trails.

The Official Story:
CSP's Sugarloaf page
Park office 707-833-5712
Team Sugarloaf page

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
Download the park brochure (pdf)
Afoot and Afield: San Francisco Bay Area, by David Weintraub (order this book from has a great map and descriptions of a Sugarloaf hike.
North Bay Trails, by David Weintraub, has an excellent map of the featured hike, and useful maps and trail descriptions of the rest of the park (order this book from
The Bay Area Ridge Trail, by Jean Rusmore (order this book from, has a decent map and descriptions of the Ridge Trail segment though the park.
Map from SonomaNet
• SonomaNet's Sugarloaf page

Sugarloaf Ridge State Park in a nutshell -- a printable, text-only guide to the featured hike.

Go to Bay Area Hiker Home page

Sugarloaf Ridge's Bald Mountain holds bragging rights to one of the prettiest and most serene viewpoints in the Bay Area.Parking lot  From a relatively diminutive height of 2,729 feet, views include every significant wine country peak and valley. At Sugarloaf Ridge every step seems like a gift. From the get-go the trails are quiet and the scenery is gorgeous-views from the top of Bald Mountain are icing on the cake.
      There's so much variety at Sugarloaf that every season has its charm. Sonoma Creek's headwaters originate here, and in winter, streams gush downhill at such a rate that you may feel transported from dry California to a more lush locale. Spring flowers are pretty and the temperatures are hospitable. Summer (if you can endure the heat) brings hillsides stacked with fragrant blooming chamise. In autumn, foliage on black oaks and big-leaf maples is stunning.
      Begin from the parking lot on Lower Bald Mountain Trail. At an easy grade, the rocky path begins to ascend from the valley floor, winding through grassland past a few coast live oak, Douglas fir, and manzanita. Look for goldenfields, buttercups, shooting stars, iris, bluedicks, and blue-eyed grass in spring. A few small ceanothus shrubs growing close to the ground suggest the presence of serpentine soil -- while it may not be obvious in this part of the park, there are significant serpentine swales visible off Bald Mountain and Gray Pine trails. After a short foray through some trees, Lower Bald Mountain Trail returns to grassland and reaches a two-part junction with Meadow Trail at 0.2 mile. Stay to the left on Lower Bald Mountain Trail. Trailhead
      The grade picks up as the path climbs into an open woodland mostly comprised of madrone, coast live oak, California bay, and manzanita. On an April hike I saw jackrabbits hopping up the trail. Switchbacking uphill between two creekbeds, the trail gradually makes a transition to chaparral, where chamise, toyon, scrub oak, ceanothus, sticky monkeyflower, and poison oak are the most notable plants. The deep umber color of the trail surface is adobe clay. This rocky segment ends at a T-junction at 0.8 miles. Turn right onto Bald Mountain Trail.
      The trail, a wide, paved road used to access communications equipment atop Red Mountain-ascends at a moderate, steady pace. Vegetation ranges from chamise, manzanita, toyon, monkeyflower, and poison oak to coast live oak and madrone. In spring, flowering purple bush lupine brightens the sides of the trail. At about the 1-mile mark, the Vista Trail departs on the right, offering an early out for hikers who are discouraged by the grade. Continue uphill on the Bald Mountain Trail. Bald Mountain Trail
      In winter and early spring, the sound of running water from a creek out of sight on the right will probably accompany your hike. Bald Mountain Trail sweeps uphill through an open area where ceanothus and coyote brush are common. At one corner, water spills downhill from the left, then drops into a ravine where buckeyes nestle. California poppies, blue and white lupine, and scorpionweed bloom along the trail in May. As the trail climbs, trailside vegetation reflects the change in elevation and exposure-there's lots of chamise, ceanothus, cercocarpus, and scrub oak. At about 1.6 miles, if you pause and look south you will already be able to see Mounts Diablo and Tamalpais. The Red Mountain Trail breaks off to the right at 1.7 miles, headed toward the Gray Pine Trail. Continue straight on the Bald Mountain Trail.
      In the shadow of Red Mountain the trail is lined with black oak, big-leaf maple, California bay, and live oaks. Buttercups are common in spring. After a swing into grassland, you'll reach a junction and saddle at 2 miles. Straight ahead the hillside drops, then gradually rises to the flanks of Mount Hood. The pavement curves left on a dead-end spur to Red Mountain. Turn right, remaining on Bald Mountain Trail. Bald Mountain viewpoint
      Now a dirt fire road, the trail adopts a moderately steep course uphill through grassland. You may notice bluish serpentine, exposed on a rock cut on the left. The grassy hillside on the right gently slips away, offering expansive views south. On an April visit, blooming popcorn flowers painted huge white swaths in spring's still-green grass. As you follow the Bald Mountain Trail, sweeping around the very top of the mountain, ignore any side trails and persist to a signed junction at 2.4 miles. Here the High Ridge Trail heads left on a dead-end journey. Turn right onto the Gray Pine Trail. After just a few feet, Gray Pine veers left. Turn right and walk uphill a few more feet to the summit.
      Interpretive signs assist you in identifying the surrounding sites: in the immediate area you can see Napa Valley, Sonoma Valley, the steep hillsides of Jack London State Park, and the more gently graded hillsides of Annadel State Park. On an April hike the top of Mount St. Helena, to the north of Sugarloaf, hid in a puffy white cloud. When visibility permits, you may also see Mount Wittenberg, the highest peak on Point Reyes (33 miles west); Snow Mountain (65 miles north, and since it is well-named, easy to pick out); Mount Diablo (51 miles southeast); Mount Tamalpais (37 miles southwest); the Golden Gate Bridge (44 miles southwest); and even Pyramid Peak in the Sierra (a whopping 129 miles east). The bench at the grassy summit offers a perch for one of the most quiet and gorgeous lunch breaks in the entire Bay Area. Save for an occasional airplane, there's no outside noise. When you're ready to start moving again, return to Gray Pine Trail and begin to descend. Gray Pine Trail
      The first section of this trail seems poorly named, as there is nary a pine in sight. On the left some towering black oaks make a big foliage impact in autumn, but in spring, train your gaze to the grass on the sides of the trail where bird's eye gilia bloom.The fire road follows just about smack on the line dividing Napa and Sonoma counties as it descends, generally following the ridgeline. You'll see more manzanita, California bay, Douglas fir, coyote brush, chamise, and toyon. In early April, blue blossom ceanothus flowers, followed a bit later by clematis, a trailing vine with white flowers, which drapes itself over shrubs. Although the route is downhill, there is one short uphill section. At 3.2 miles Red Mountain Trail ventures off to the right -- you could make an alternate return on Red Mountain, Headwaters, and Vista trails. For this hike, continue straight on Gray Pine Trail.
      Descending at a slightly steep pitch, look for woodland star, buttercups, and blue-eyed grass in spring. Black oaks, chaparral, and grassland continue to line the trail, but the first of the gray pines appears as well. After one last hill climb, you'll reach the junction with Brushy Peaks Trail at 3.6 miles. Turn right, remaining on Gray Pine Trail. Gray Pine Trail
      By now the trailside blend of chamise, cercocarpus, ceanothus,scrub oak, manzanita, and monkeyflower should be familiar. Tall and spindly gray pine (also known as ghost pine) tower above the trail here and there-if you're hiking when it's a bit breezy, you may want to pause and enjoy the sound of the wind whispering through them. Descending off the ridge, the grade is steep, and some sections are very rocky. Gray Pine Trail leaves its namesake trees behind and arcs through a grassy area, where wet-weather runoff flows down off the hillsides and muddies the trail. Now following a branch of Sonoma Creek, still descending but at an easy grade, madrone and coast live oak appear. After a sharp turn left, you'll cross another feeder creek. Look along the sides of the trail for golden fairy lanterns in late April and early May. Wandering along the creek through this flat creek basin during a spring hike with the sounds of rushing water everywhere, I felt like I was on an alpine vacation. Gray Pine Trail makes its first creek crossing-in the warmest months of year you can hop over whatever water is left in the creekbed, but from winter through spring the water level is high enough that your feet (and ankles) will likely get wet. I took off my shoes and socks and waded across the cool water, and my feet felt like they had been given a whole new lease on life. Buckeye, alder, and California bay stand near the creek, enjoying the reliable water source. At 4.8 miles Vista Trail feeds in from the right. Continue to the left on Gray Pine Trail.
     At the second creek crossing there is generally even deeper water to ford. A gorgeous mature big-leaf maple graces the stream here -- if you're here in spring when the tree is clothed in fresh green leaves, you'll have to imagine it lit up with autumn foliage. Gray Pine Trail ends at 5 miles. Turn right onto Meadow Trail. Gray Pine Trail
      From here on out, the grade is very easy, a relaxing stroll, really. Once more you'll cross Sonoma Creek (this time on a bridge), then pass through groves of maples. A curious "Saturn" sign on the left is part of the Planet Walk interpretive hike that originates at Ferguson Observatory. The creek veers off to the left, continuing its journey toward Sonoma Valley, but the trail leaves the streamside to make its way through a meadow. Some chaparral thrives in a serpentine patch on the right, but grassland soon overtakes the landscape. The meadow is yet another super scenic Sugarloaf spot-this would be a good location for a bench, since both grass and trail are often damp in winter and spring. At 5.7 miles Hillside Trail breaks off to the left, heading back over Sonoma Creek toward the park's campground. Continue straight, through or around a gate, where you'll emerge in a parking lot. Veer right, passing Ferguson Observatory, and pick up the continuation of Meadow Trail.
      On a slight ascent through a rocky area, another feeder creek descends on the left. Goldenfields make a big impact along the trail in spring, when they form sunny carpets in the grass. In patches of serpentine with sparse grass, you likely see more bird's eye gilia. Here on my April hike I had another jackrabbit sighting. At 5.8 miles you'll reach a two-part, triangle junction with Lower Bald Mountain Trail. Stay to the left, and retrace your steps back to the trailhead.

Total distance: 6.2 miles
Last hiked: April 30, 2003