Summit Rock, Sanborn & Castle Rock Loop Hike
Details
➤ Hike Description: A 7.49 mile, 1,713 feet of elevation gain moderate loop starting at Summit Rock. Summit Rock is a year-round habitat and nesting site for Peregrine falcons. To protect nesting birds, access to Summit Rock is restricted to weekends and holidays from September 1 to January 31. Once nearly extinct due to the pesticide DDT, Peregrine falcons have made a remarkable recovery thanks to conservation efforts. They are now found on every continent except Antarctica, nesting on cliffs, skyscrapers, and bridges. Their presence at Summit Rock is a testament to the success of these conservation initiatives.
We'll also visit other rock formations popular with climbers, where we may see them practicing their skills. These formations include Indian Rock Boulders, Hash Boulder, Clamshell Boulder, Castle Rock and Goat Rock. Some short trail sections require rock scrambling.
Our snack break will be at the Interpretive Center adjacent to the Robert H. Geisler Woodland Grove. This site, once part of the Partridge farm, features some remaining fruit trees, shaded and sunny picnic tables, and trash receptacles. Newly installed interpretive panels provide information about the area's geology, wildlife, habitats, and park history.
➤ Post-Hike Potluck: We invite you to join us after the hike for a festive tailgate potluck gathering at the area adjacent to the parking lot. Pizza, smoked salmon and assorted drinks provided. Glass containers and alcohol are not allowed in Sanborn at our picnic location, so exercise the better part of valor.
➤ Route:
· Parking lot to Skyline Trail (Bay Area Ridge Trail): 0.5 miles
· Summit Rock Trail: 0.2 miles
· Summit Rock Loop Trail: 1.1 miles
· Indian Rock Trail: 0.4 miles
· Highway 35: 0.1 miles
· Castle Rock Trail: 0.9 miles
· Saratoga Gap Trail: 0.3 miles
· Ridge Trail: 0.3 miles
· Goat Rock Trail: 0.5 miles
· Ridge Trail: 1.1 miles
· Interpretive Trail: 0.2 miles
· Service Road Trail: 0.1 miles
· Loughry Woods Trail: 1.7 miles
· Skyline Trail back to parking lot: 0.1 miles
A route map is provided in the photos along with some of the 1/5/2025 scouting pictures. If you have an account you can view and download the route map on GAIA or AllTrails.
➤ Directions/Parking: We meet at the Summit Rock parking lot off Highway 35, 1.5 miles south of Saratoga Gap (junctions of highways 35 and 9). Parking is free.
GPS: 37.2417497, -122.1058078
37°14'30.3"N 122°06'20.9"W
➤ Restrooms: Vault toilet at Castle Rock and Castle Rock trail camp, none at the trailhead. No water at trailhead or along the route. Flush toilets and water are available at the main Castle Rock entrance (Robert C. Kirkwood entrance) one mile south on Highway 35.
➤ Exposure: 85% covered under mixed oak and old growth redwood, 15% exposed on western hillsides. Weather forecast at AccuWeather.
➤ Cell Phone Coverage: Spotty coverage throughout the park. Wi-Fi available at the nearby Robert C. Kirkwood entrance to Castle Rock.
➤ Carpools: Requesting a carpool in the comments is okay. Replies to the initial request are to be through private message to the sender only.
➤ Attendance: This is a Sierra Club back country outing requiring a completed paper Outings Medical Form. This form can be downloaded from the Sierra Club website. Bring this form with you. Please arrive by 8:45 to sign the waiver and be ready to hike at 9:00. If this page has a wait-list you can sign in on the Sierra Club calendar.
➤ Park websites: Castle Rock State Park - Sanborn County Park
➤ Bring: Medical form completed. Lunch, water, a sit-upon for lunch, warm layers, sturdy boots and poles if you use them, sun protection, dish and/or sparkling personality for the potluck if you’re staying. A camp chair if you have one for the potluck.
➤ Safety: We will hold a safety meeting prior to the hike. You hike at your own risk and are responsible for your own actions. Nearest emergency services from the Cal Fire CZU station 2.2 miles NW on Highway 35. Castle Rock phone number: (408) 868-9540. In case of emergency, call 911.
➤ Sierra Club guide for our hike outings: Neither vaccinations nor masks are required. But if you are experiencing any COVID symptoms, are sick, or have recently tested positive for COVID do not hike with us on this day. Any participant is responsible for reporting these conditions to the leader if symptoms develop after they hike. We will then notify the other participants.