Castle Rock State Park,
California State Parks,

Santa Cruz County
In brief:
5.49 mile partial loop near the highest point in the Santa Cruz Mountains. One of the best hikes in the Bay Area, it offers outstanding views west, pretty oaks, woods, and chaparral, and unique sandstone formations.

Distance, category, and difficulty:
Overall, this 5.49 mile partial loop hike is moderate, with about 1000 feet in elevation change. Trailhead elevation is about 3090 feet. The featured hike descends to about 2300 feet, then gradually ascends back to the trailhead. Some short sections of trail are steep, and there are portions of Saratoga Gap Trail that require brief scrambles on narrow exposed paths with sharp dropoffs.

Shaded and the beginning and end, mostly exposed in the middle.

Trail traffic:

Trail surfaces:
Dirt trails, with some rocky scrambling on Saratoga Gap Trail.

Hiking time:
3 hours.

Good all year -- waterfalls at peak in late winter and spring.

Getting there:
• From Interstate 280 in San Mateo County, take CA 92 west, then turn south onto Skyline Boulevard (CA 35).  Drive about 25.5 miles, to the junction of 35 and 9 (Saratoga Gap). Continue about 2.5 miles further south on 35, to the park entrance on the right side of the road.
• From CA 85 in Santa Clara County, exit Saratoga Avenue. Drive west into Saratoga, then continue uphill on CA 9. At Saratoga Gap (junction 9 and CA 35), turn left and drive south about 2.5 miles to the park entrance on the right side of the road.

Street address (for in-transit navigation):
15000 Skyline Blvd., Los Gatos, CA 95033

Get driving or public transit directions from Transit and Trails:

GPS coordinates* for trailhead:
Latitude 3713'50.39"N
122 5'45.01"W
(* based on Google Earth data, shown as degrees, minutes, seconds)

Gas, food, and lodging:
There are no services in the immediate area, but you can find gas, stores, and restaurants on CA 9 either east in Saratoga, or west in Boulder Creek. The Castle Rock backpack camp is for many the start of the long Skyline to the Sea Trail trip, but Castle Rock does not have a drive-in campground.

Trailhead details:
Large parking lot, and some free roadside parking just past the entrance on the right side of the road. Mind the no parking signs at the pullout. There is a day use entrance fee of $8/$1 for seniors (additional fees apply if you leave your vehicle in the lot overnight). There are two designated handicapped parking spots in the parking lot, but the trails are not suitable for wheelchairs or strollers. Pit toilet on north side of parking lot. Pay phone in lot. No drinking water at the trailhead or on the trail. Maps are available for $2.00 when kiosk is staffed; there is a map under glass at the information signboard on the south side of the parking lot, just past the entrance. There are other walk-in entrances to Castle Rock with little parking: on Skyline Boulevard near Sanborn-Skyline County Park's Summit Rock, several pullouts on CA 9, and from Saratoga Gap, where there is a parking lot (not managed by the parks department), but no other amenities. There is no direct public transportation to the park.

Dogs and bicycles are not permitted in the park. Horses are allowed on some trails, but others are signed hiking-only. Trails close at sunset.

The Official Story:
CSP's Castle Rock page
Park office 408-867-2952

Map Choices:
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
Park brochure (with map) pdf
• Order the Saratoga to Big Basin map from Redwood Hikes.
• South Bay Trails, by Jean Rusmore, Betsy Crowder, and Frances Spangle (order this book from has a simple map and trail descriptions.
The Bay Area Ridge Trail, by Jean Rusmore (order this book from has a good map and descriptions of Castle Rock's Ridge Trail segment
The Santa Cruz Mountains Trail Book, by Tom Taber, has a simple map (order this book from
• Trail Map of the Santa Cruz Mountains (map 1), by the Sempervirens Fund (includes Castle Rock, Big Basin, and Portola Redwoods) has a great map of Castle Rock.

Castle Rock in a nutshell -- a printable, text-only guide to the featured hike.

View 38 photos from this hike (shorter version; autumn hike on Ridge Trail, connector path, Saratoga Gap Trail, and Castle Rock Trail).
View 71 photos from this hike (longer version; winter hike on Ridge Trail and Saratoga Gap Trail).

Go to Bay Area Hiker Home page

When I look at a trail map Castle Rock parking lotof the Skyline-to-the-Sea route from Saratoga Gap to the Pacific Ocean, it's hard for me to grasp the magnitude of that hike: it's 32 miles (one way) and the elevation drops about 2,600 feet, with lots of ups and downs along the way. From the Saratoga Gap Trail at Castle Rock State Park, the backdrop to this awesome adventure is laid out at your feet. Although the trail is not visible, you can see the miles of rolling, forested hills that lie between Skyline Boulevard and the Pacific Ocean. Castle Rock is unique; in addition to the park's stunning rock formations and beautiful views, it's a staging area for long journeys to the sea, or just for great day hikes lasting a few hours.Tafoni off Saratoga Gap Trail
     From the Saratoga Gap trailhead, you can take a short out-and-back hike along CA 9 on Skyline-to-the-Sea Trail, or make a loop out of Saratoga Toll Road, Travertine Springs Trail, and the Saratoga Gap Trail, a more than 10 mile trek. For a backpacking excursion, you can hike from the park's main entrance into Castle Rock Camp, stay overnight, then continue west into Big Basin State Park. On the opposite extreme, the shortest loop at Castle Rock is less than a mile, and combines Castle Rock and Saratoga Gap Trails.
     This park is popular with rock climbers, and can get busy in warm weather. Voices carry far here, and the park also gets an unwelcome dose of noise pollution from the gun club about 1 mile north of the park entrance on Skyline Boulevard.Satatoga Gap Trail I prefer visiting in winter, when the views to the west are clear, and the weather cool. The gun club is also quieter in the winter, especially if weather is cold and rainy. Keep in mind that it can get bone-chillingly cold in this part of the Santa Cruz Mountains, particularly in the heavily forested area near the main park entrance. Temps in the 20s are not uncommon in the winter months, and neither is snow. Dress accordingly, and be careful on the roads, which can get icy. 
      Castle Rock is not a park I would recommend to beginning hikers, or those with mobility problems. The trails are narrow, the drop-offs sharp, and the some of the trails can be slippery. Although most of the trails are straight-forward, some segments are somewhat technical. Ridge Trail It's a tough place for knees and hips, as you must scramble up and down some boulders and navigate steep sandstone shoots. This doesn't mean you shouldn't go if you're in good shape, because the views from Saratoga Gap and Ridge Trails are worth a few sore joints. A trekking pole (or two) is definitely recommended.      
     This featured hike travels through a lovely oak savannah and chaparral-studded hillsides, under California bay, madrone, tanoak, and Douglas fir, and past the fascinating sandstone rock formations known as tafoni. Start in the main parking lot and look for the start of the Saratoga Gap Trail to the west, near an information signboard and two low, red-painted barricades. Saratoga Gap Trail initially runs along a seasonal stream, Curve in trail near a boulderunder a heavily shaded tanoak, madrone, and Douglas fir forest. At 0.17 mile, Castle Rock Trail departs from the left side of the trail at a signed junction. Continue downhill on the Saratoga Gap Trail.
      The trail skirts a large rock that bulges out onto the path. The easy downhill grade stiffens a bit. From time to time, particularly during stormy months, fallen trees make the trail an obstacle course. As a perennial stream joins the (usually) dry creek, Saratoga Gap Trail crosses over the stream, and then at a signed junction meets Ridge Trail at 0.67 mile. Look for wild ginger and giant chain fern along the creek. Take Ridge Trail, right, uphill.
         The narrow path ascends, passing a large, white rock outcrop and moss-covered live oaks. After only a few moments, the trail leaves the woods and enters chaparral. Look for chamise, pitcher sage, varieties of ceanothus, California coffeeberry, manzanitas, and toyon. In winter, a single flowering currant puts forth pink blossoms on the right side of the trail at a shady spot. The views west are breathtaking. Oak woodlandRidge Trail commands your attention, as tree roots amble across the path like sleeping swollen snakes, and the trail, smooth and sandy one minute, a pile of boulders the next, is one surprise after another. On the right side of the trail, a large outcrop, know as Goat Rock, is visible uphill. Steps are cut into some soft rock in one section. At another area, there is a pile of boulders under the cover of a coast live oak, and the trail is a bit confounding. "The trail is where?" you may ask, particularly in the winter when leaves cover the path and foot traffic is limited, making it difficult to see where others have gone before you. Like a few other confusing trail sections, if you take it one step at a time the routing is obvious; it's just impossible to see ahead more than a few feet. Madrones on Ridge TrailThe toughest call is an unmarked junction of sorts, where a legitimate-looking trail seems to continue on a level course straight ahead, and an unlikely-looking rock pile heads uphill on the right. Pick your way up the rocky slope, and the trail becomes evident again. Follow the trail sign, staying to the right at another confusing non-junction, and continue uphill. Wooden fencing and steps constructed in 2000 improve the final ascent to Goat Rock, which previously was a steep, undefined hillside scramble. At the top of the hill, at 1.17 miles, you'll reach the top of Goat Rock and two signed junctions (one to the right and one to the left). Bear left and after a few feet, at another junction, bear right on Ridge Trail, "to Campground." (Option: at the top of the steps near Goat Rock, turn right and take the trail marked "to Interpretive Center." The path edges near rocks very popular with climbers, and then cuts through a grassy oak-studded slope to the Interpretive Center. View from Ridge TrailExhibits in the open-air pavilion include a treatise on sandstone formations, identification drawings of the 7 types of oak found at Castle Rock, and a rudimentary trail map. Exit to the north and look for Ridge Trail, signed "to campground.")
     Black oaks and California bays mingle with madrones as the trail winds levelly through grassland. Looks like feral pigs have invaded the park in a big way, for the ground beneath the oaks was completely "pig rototiled" on one visit. At 1.36 miles, Ridge Trail meets the path from the Interpretive Center at a signed junction. Bear left to stay on Ridge Trail.
     This narrow trail cuts through grassland, gently descending under some live and black oaks, and madrones. Stay to the right as a faint trail breaks off and heads west, to a bird-watching viewpoint.View from Ridge Trail I love walking through here in the winter, when it is quiet (at least as quiet as it ever gets) and many fallen leaves from the deciduous oaks litter the trail. As a transplanted easterner, I delight in the crunch of leaves underfoot, and that smell that defines autumn for me. At 1.66 miles, you'll reach a signed junction with a connector to Saratoga Gap Trail. Continue straight on Ridge Trail, "to campground." (Option: to shorten this hike, take the trail to the left, signed "to Saratoga Gap Trail."  The connector trail between Ridge Trail and Saratoga Gap Trail winds downhill; turn left onto Saratoga Gap Trail at a signed junction and follow the remaining instructions below.)
     The trail continues to lose elevation at a gradual pace as it descends just downslope from a ridgeline. The trail skirts a rock formation, where manzanitas seem to be dying out, their sunlight blocked by encroaching trees. Tanoaks, live oaks, and madrones dominate, but the trail also passes beneath a small grove of very tall pines. Somewhat abruptly, Guidewires assist hikers down the edge of a boulderRidge Trail steps out from the trees to a viewpoint at the edge of the ridgeline. The sheer rocky drop is softened by thick stands of buckbrush, manzanita, and chamise. Ridge Trail pops back under tree cover, but then draws near the cliff again, where a wooden fence guards against what would be a nasty fall. This is my favorite viewpoint, and a nice spot for lunch on a sunny day. The trail sweeps back into the woods, and continues a descent toward the campground. At 2.60 miles, Ridge Trail meets Saratoga Gap Trail at a signed junction. Turn left onto Saratoga Gap Trail.
     Tanoaks and madrones line the hiking-only trail, which soon takes a sharp turn left and leaves the forest. Saratoga Gap Trail narrows as it creeps beneath a rocky outcrop still somewhat shaded by live oaks and California bays. A metal guidewire helps you navigate a short steep drop over a small boulder. Then the path edges along an exposed hillside, with wonderful views to distract you from the demanding trail. Manzanitas, ceanothuses, and chamise dominate, but look for silktassel, lupines, coyote brush, Saratoga Gap Trailyerba santa, and monkeyflower as well. There's another tricky section of trail where you must scramble up and then down a small outcrop. Saratoga Gap Trail makes a transition into oak grassland, where poison oak is common in the understory. This area is lovely in autumn, when black oak trees put on a foliage show. At 3.70 miles, Saratoga Gap Trail meets the connector path to Ridge Trail at a signed junction. Continue straight on Saratoga Gap Trail.
     A patch of sagebrush flourishes on the left, and a few buckeyes huddle together in a little gulch on the right. The trail leaves oak grassland and returns to chaparral. There are nice views to the rock formations on the hillside near Goat Rock. Saratoga Gap Trail crosses through a California bay wood near a stream, where a bench sits just before a narrow bridge. There's no view from here, but it's nice and shady.Tafoni on Saratoga Gap Trail Look for a small young redwood grove on the right. After crossing the stream the trail climbs slightly, passing a handful of madrones, which in winter drop curled strips of bark that look like cinnamon sticks. As the trail crests, it veers left and edges along the side of the mountain, through chamise, manzanita, ceanothuses, and aromatic pitcher sage. Saratoga Gap Trail follows the contour of the slope and features views to the north and southwest. You may glimpse bobcat and coyote tracks on the trail, some brief sections of which are steep and awkward to negotiate. Even before spring reaches Castle Rock, some plants enliven the chaparral with their blossoms. Manzanitas put forth urn-shaped flowers around late February, and you might also see blue-witch nightshade and Indian paintbrush at that time. Buckbrush and wartleaf ceanothus generally bloom in March. There are a few flat rocks on the west side of the trail, perfect perches on which to sit and stare out into space. Rocky maze on Saratoga Gap TrailI have one flat boulder I call my sitting rock. It's a meditative spot, peaceful and serene. On a December hike I watched two hawks fly so far up in the sky I could barely follow their movements. I wished I could join them; something about this view makes me want to fly. On the east side of the trail, across from my special rock, there's a well-preserved tafoni formation. If you stop and sit on this rock, or any other, be careful not to fall off the side of the hill! Saratoga Gap Trail tapers off to a mostly level grade. Along the trail occasionally a few California bays provide a little shade. The path squeezes between two boulders, and then begins a return to a California bay, live oak, Douglas fir, and tanoak forest. On the left side of the trail two huge old live oaks seem to be growing out of a patch of moss-covered boulders.Castle Rock Falls You must climb through a pile of large rocks, a rather illogical stretch of trail which seems to me could have been routed down the slope a bit. In late winter, look for the delicate flowers of wild strawberry, nestled close to the ground. Sounds of rushing water drift down the trail, indicating that you're nearing the falls. For the best view of Castle Rock Falls, hop down onto the viewing platform on the right side of the path at 4.66 miles. From there you'll have a view of the water as it sluices through a rock channel and then drops 75 feet or so. Even before the storms rage in the winter, this waterfall is active.
        Continue up Saratoga Gap Trail to the previously encountered junction with the Ridge Trail, at 4.82 miles. Turn right and retrace your steps uphill on Saratoga Gap Trail. (Option: when you reach the signed previously encountered junction with Castle Rock Trail, turn right. This gently graded path meanders uphill underneath oak, California bay, madrone, and Douglas fir to the tafoni formation known as Castle Rock. TafoniThe rock is large and impressive, although unfortunately the area surrounding it is sometimes defiled with broken bottles, so step carefully. Castle Rock juts out from a flat spot, like a fairy tale mansion, and the formation may set your imagination in motion. Weird stone pockets look like secret caves, and rock cascades off the side like a cresting wave. When you're done daydreaming, continue on Castle Rock Trail, pass another group of large boulders off to the right side of the trail, and then as a fire road continues straight, turn left toward the parking lot at a signed junction. Follow the trail back to a fork, and then take either branch to return to the parking lot.)

Total distance:  5.49 miles (6 miles if you decide to visit Castle Rock)
Last hiked: September 24, 2013
Previous visit: March 5, 2002