Castle Rock State Park 50th Anniversary

50 years of Castle Rock State Park

Castle Rock State Park lies along the skyline of the Santa Cruz Mountains, a cool, pacific oasis for people seeking to escape the frenetic pace of Silicon Valley. It exists because a high tech pioneer and others with an abiding love of the outdoors understood its unique value in restoring the human spirit.

As rugged and uncivilized as Castle Rock can be, it has always been a place humans came for renewal. For time immemorial, the Amah Mutsun and Muwekma tribal bands used the area as a stopover point on their treks from the valley to the ocean. More recently, western pioneers also saw the Castle Rock forests as a comfortable resting spot in their search for new lives.

What these visitors found was a majestic area of redwood, bay, fir, oak, and madrone punctuated with small caves carved naturally into sandstone. Castle Rock itself crowns the ridge on which it sits. The views inspire awe as well as contemplation. To the west and south lie the Pacific Ocean and Monterey Bay. To the east is the Santa Clara Valley.

Among those who found refuge in the mountains after the turn of the century was John Varian of Palo Alto, who would often gather sons Russell, Sigurd, and Eric and assorted friends for hiking expeditions. Those trips, sometimes on foot, sometimes on horseback, spawned in Russell a love of nature that grew into a vision of a state park that would enable future generations to, as he later put it, “find anew the values that are ages old.”

There is no irony in the fact that a successful scientist and inventor who lived in a world of facts and numbers would devote so much of his life to preserving and enhancing nature. Russell Varian’s invention of the klystron power tube brought into being modern radar and led to the development of space-age communications. The klystron and his work on nuclear magnetic resonance technology formed the basis of Varian Associates, the pioneering high-tech company he created in 1948 with brother Sigurd and others. But Russell Varian’s scientific advances were drawn from a wide range of sources including, as one scientific colleague put it, “something better than thinking.” The wilderness was one of the most important wellsprings of his creativity.

Russell Varian seldom went to the wilderness alone. His wife, Dorothy, grew to love Castle Rock as he did. Their dream of helping to create Castle Rock State Park was part of a shared vision.

In 1959, Russell Varian obtained an option to buy the land surrounding Castle Rock through the Sierra Club. Sadly, he died before the purchase could be completed. By 1968, the Varian Foundation had acquired 513 acres and established the first segment of Castle Rock State Park.

That same year, Sempervirens Fund was reborn from the roots of the dormant Sempervirens Club, and in its modern form began raising funds for acquisition of park lands to extend all the way from Castle Rock to the Pacific Ocean. Today, Castle Rock encompasses 5,242 acres and boasts 34 miles of trail.

“This is an amazing park,” said Sara Barth, executive director of the Sempervirens Fund. “It has always rested at the nexus of the wild and the wild imaginations of Silicon Valley.”

To celebrate the 50th Anniversary of Castle Rock State Park, Sempervirens Fund is planning a slate of events, including a monthly lecture series with partners REI, a public celebration of the park in September and the grand opening of a brand new, state-of-the-art park entrance.

A New Park Entrance for the 21st Century

For many years, Sempervirens Fund has envisioned a grand entrance welcoming local residents and visitors to the redwood forests of the Santa Cruz Mountains. In 2011, generous contributors supported the purchase of a 33-acre parcel from the Whalen Family. State Parks had long identified this site as the ideal entrance for Castle Rock State Park, the “gateway” to the Santa Cruz Mountain redwoods. After community meetings, design revisions, and traffic and environmental assessments, Santa Cruz County approved our two-phase conceptual plan (which includes a future 6,000sf visitor center as Phase 2) in September 2014. Since that time, the property’s zoning has been changed from agricultural to open space and recreation, additional assessments and plans were produced, and the necessary permits for Phase I improvements were finally secured in March 2017.

Thanks to ongoing support from individuals and foundations, Sempervirens Fund was able to approve a $5 million contract with the well-respected local builder Robert A. Bothman, Inc. Construction. The new Robert C. Kirkwood entrance includes a 90-car parking lot with permeable paving, 6 restrooms with flush toilets, a drinking water station, 60-seat amphitheater, accessible pathways and picnic areas, and native landscaping (including an ethnobotanical demonstration garden, by the Amah Mutsun Land Trust). There will also be interpretive exhibits, WiFi connectivity,  and new engagement opportunities. Construction will continue – weather permitting – throughout the next several months, and we anticipate opening sometime this summer.

Creating this new entrance is a fitting way to mark the anniversary of Castle Rock State Park, which turns 50 years old in 2018. We look forward to celebrating this beloved park and walking with you through its new entrance later this year!

For construction updates and details for our last Wednesday Lecture Series, visit

To support construction, interpretation, and engagement programs at the Kirkwood Entrance, donate here.

Some exciting naming opportunities are still available. Contact our Donor Services department at (650) 949-1453 x1 or if you would like to add your support, or honor someone, at this new park entrance.


Related news articles:


See all the Sempervirens Fund Anniversary Picnic and Castle Rock Groundbreaking photos on Facebook.

Additional Project Renderings:

Robert C. Kirkwood Entrance at Castle Rock State Park.

Robert C. Kirkwood Entrance at Castle Rock State Park. Callander Associates/Sempervirens Fund


Graphic rendering. Callander Associates/Sempervirens Fund


Graphic rendering. Callander Associates/Sempervirens Fund


Graphic rendering. Callander Associates/Sempervirens Fund

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