Castle Rock State Park

Castle Rock is a small park with a big personality. On one of the highest ridges in the Santa Cruz Mountains, honeycombed sandstone boulders poke out of a forest of Douglas fir, madrone, black oak and high-elevation redwoods. Climbers have worked these rocks for nearly a century. Hikers come for a seasonal waterfall, long views toward Monterey Bay and the start of the Skyline to the Sea Trail.

California State Parks manages the park. Our waterfalls guide and fall colors guide each give it a section. This page goes further: the hikes with published distances, the climbing rules, the trail camps, fees and hours, the rules on dogs, bikes and horses and the Palo Alto connection behind the park's creation.

Getting there

State Parks puts the park on Highway 35 (Skyline Boulevard), 2.5 miles southeast of the junction with Highway 9. From Palo Alto, take Page Mill Road up to Skyline and turn left. Follow the ridge south about 7 miles to Saratoga Gap at Highway 9, then continue 2.5 miles to the main entrance on the right. Plan on about 50 minutes. Highway 9 from Saratoga is the other way up.

The main entrance is the Robert C. Kirkwood parking lot. State Parks warns there is no cell reception in the park or the area around it, so ridesharing home is not recommended. There is also no visitor center or store.

Fees and hours as published

State Parks notes that special rates may apply on peak weekends and holidays and that prices can change without notice. Check the official park page for the latest. The park page lists drinking water as available.

Status on October 30, 2026

• Trails: open.
• Climbing: open.
• Trail camp: open, with no campfires.
• Camping reservations: State Parks said backcountry trail camps were reservable.

Climbing status changes quickly with the weather. Under District Superintendent Closure Order 715-002-20, any measurable rain at the Castle Rock Kirkwood office can close the climbing areas for up to three days. With the rainy season starting, expect closures after storms.

Hikes and the waterfall

State Parks counts 34 miles of rugged trails in the park, linked to a larger network running to Big Basin and the Midpen preserves. Its published routes from the main parking lot:

Castle Rock Falls

The short walk most people come for drops downhill to a viewing platform above 75-foot Castle Rock Falls. State Parks says it gushes after rains but may be a trickle in drought. The westward views are spectacular either way. Remember that the climb is on the way back. Stay behind the railing; the rock beyond is steep and slick.

Goat Rock and the Ridge Trail

Continue past the falls on the Saratoga Gap Trail and you cross a steep, open hillside to the junction with the Interconnector and Ridge trails, passing the sculpted sandstone of Goat Rock. The Goat Rock overlook looks over the San Lorenzo Valley toward the Pacific. State Parks says the Ridge Trail may give you a glimpse of the park's peregrine falcons. An interpretive shelter on the Ridge Trail has exhibits on history and wildlife. The Russell Point Overlook is on the longer loop.

Longer routes from Saratoga Gap

The Middle of the Park from the Gap Loop runs 9 miles with 1,530 feet of gain. The Gap to Gap Loop covers 16.4 miles. The historic Saratoga Toll Road, a logging road and stagecoach line from 1871, is now a shaded, graded trail. The full Skyline to the Sea route to Waddell Beach is listed at 25.2 to 28.2 miles, but in October 2026 State Parks said the trail was open only as far as the Big Basin day use area.

Rock climbing and bouldering

State Parks says climbers have scaled the park's outcrops of Vaqueros sandstone, Castle Rock and Goat Rock, for nearly a century. The hard outer skin and the honeycomb patterns called tafoni make the rock good for bouldering and roped climbing. The smaller rocks around Castle Rock itself are also a natural playground for kids.

The park requires low-impact climbing. Its rules:

1. Do not chip, glue, remove or otherwise alter the rock. Leave the tafoni undamaged.
2. Wait two or three days after heavy rain, or until the rock is completely dry. Wet sandstone breaks.
3. Notify the park and get approval before placing or replacing any bolt.
4. Use only existing access trails and carry crash pads rather than dragging them.
5. Do not climb in the San Lorenzo Headwaters Natural Preserve. Check bulletin boards for closures to protect nesting birds.
6. Spread out when a route is crowded. Large groups have large impacts.

Climbing classes, including those run by schools and nonprofits, need an advance permit and insurance; State Parks lists (831) 345-2519 for applications. If you are new to climbing, start indoors. Our climbing gyms guide lists places near Palo Alto.

Trail camps

Castle Rock Trail Camp sits on a ridge 2.6 miles from the main lot via the Saratoga Gap Trail. State Parks lists 20 sites with picnic tables and fire rings, vault toilets, trash cans and a shelter for bad weather. Fees are $15 per site per night for up to six people, with overnight parking for one car, plus an $8 nonrefundable reservation fee. Five sites are kept first come, first served; register and pay at the Kirkwood lot before you hike in.

Fires are allowed only in the camp's metal rings during the rainy season. In late October 2026 the park listed the camp as open with no campfires. Firewood costs $15 a bundle when fires are allowed. Gathering wood is prohibited. The hiking page mentions water at the camp, but the trail camp rules tell backpackers to bring their own or treat surface water, so carry it.

Waterman Gap Trail Camp has six primitive sites and a vault toilet, 6.3 miles from Saratoga Gap. There is no overnight parking at Waterman Gap, so many backpackers walk 9.3 miles in from the main entrance. No fires are allowed there, but gas stoves are.

Reservations for both open up to 60 days ahead through the State Parks trail camp request form. A request is not a booking until you pay by phone at (831) 338-8867, Monday through Friday from 1 to 5 p.m. Our camping guide compares other campgrounds.

Dogs, bikes, horses and other rules

• Dogs: prohibited throughout the park, except service animals. State Parks suggests nearby Sanborn County Park, which allows dogs.
• Bikes: allowed on the Skyline Trail (Bay Area Ridge Trail) on the north side of Highway 35. Cyclists can reach the trail camp only by the Campground Service Road Trail off Highway 35; no bikes on trails beyond it.
• Horses: allowed on the Saratoga Toll Road from Saratoga Gap toward Big Basin. No horses in the trail camps.
• Prohibited: drones, glass containers, smoking anywhere in the park and firearms or any device that can hurt a person or animal.
• Leave it: do not pick wildflowers or mushrooms, remove anything or mark rocks.
• Crumbs: the park is part of State Parks' Crumb Clean campaign to protect the endangered marbled murrelet, which nests here. Jays and ravens drawn to dropped food raid murrelet nests.

History and a Palo Alto connection

State Parks says the land was home to Ohlone communities, who used the massive rocks for spiritual practice and gathered medicinal and food plants. Logging came with the Gold Rush; by 1884 there were 28 lumber mills in the Big Basin and San Lorenzo Valley area. Orchards followed. Heritage fruit trees planted by the Smead and Partridge families in the early 1900s still bear fruit near the interpretive shelter.

In 1908 Judge Joseph Welch bought 60 acres on Castle Rock Ridge and opened it to the public. Later the physicist Russell Varian, who explored these canyons as a young man, secured an option on the land in 1959 to give to the state. He died before the purchase was finished. The Sierra Club and the Sempervirens Fund donated the land in his memory. Castle Rock became a state park in July 1968. Varian co-founded Varian Associates in Palo Alto; see our Varian company page.

Safety and what pairs nearby

Pair the park with a Ridge Trail walk at Saratoga Gap, the quiet loop at Long Ridge or the redwoods at Big Basin, covered in our redwood forests guide.

Frequently asked questions