Castle Rock State Park sits atop the crest of the Santa Cruz Mountains and includes rugged terrain left mostly in its natural state and crisscrossed by many trails popular with backpackers and horseback riders. The park is located on Highway 35, just 2.5 miles southeast of the junction with Highway 9. Phone (408) 867-2952 for more information.
The Whole Access Trail is about 0.08 mile long and leads to an outstanding vista and picnic area. The trailhead is located at the Castle Rock parking lot. Parking and a pit toilet are usable. A picnic table at the end of the trail is usable.