Marin County to get long-sought King Mountain property

A campaign to preserve hundreds of acres in central Marin County is culminating after more than 40 years.

The King Mountain Open Space Association, formed by a group of Larkspur residents, led an effort in 1989 to purchase 131 acres of the 292-acre property for $3.4 million. The agreement also secured a scenic and open space easement protecting 129 acres from development, and left 32 acres at the summit of the 780-foot mountain vulnerable to development.

That is about to change.

The Shelby Cullom Davis Charitable Fund, a private family foundation based in Delaware, has offered to cover the purchase of the remaining 161 acres and also throw in $2 million to help pay for its stewardship. The money will come in handy because King Mountain's native plants are being threatened by invasive French broom.

Carl Somers, chief of planning for the county parks department, briefed the Marin County Parks and Open Space Commission on the development on May 21.

"The Marin Open Space Trust and the charitable fund managed to negotiate a purchase of the property," Somers said. "So we're pretty much lined up to go to the Board of Supervisors in July with the donation agreement."

King Mountain is in the eastern foothills of Mount Tamalpais just above Larkspur and bordering Kentfield. Somers said the property features panoramic views from the summit and a mosaic of vegetation: redwood, bay, Douglas fir, coast live oak and eucalyptus trees, and chamise, madrone, manzanita and coyote bushes.

"Very few people have ever been up on the summit of the mountain," Somers said. "It has always been off limits."

The plan is for the Marin Open Space Trust to immediately convey ownership of the property to the county once the purchase is complete. Somers said one of the first things the parks department will do is remove the chain-link fence that bars entry to the summit.

Several members of the King Mountain Open Space Association attended the commission meeting.

"I was up there this morning. I go up on that little trail two to three times a week," said Larkspur resident David Moller, the association president. "I took a selfie in front of the gate."

Moller, 74, was 34 years old when he helped found the association. It formed after Larkspur moved to downzone its 131-acre share of the property, paving the way for development in 1985.

"We convinced the City Council to hold a town hall meeting," Moller said. "We had no idea how many people would come. Over 400 people showed up."

Don Dickenson, a county planner at the time, said that several years earlier the county approved a master plan allowing one residence per 20 acres on 161 acres of the property in the unincorporated area.

At the time, it was the lowest residential zoning density in the county, but it would have allowed the property to be subdivided into eight lots.

Supervisor Gary Giacomini, who helped prevent housing subdivisions in West Marin by spearheading a push for one-dwelling-per-60-acre zoning in agricultural lands, got the county involved in the effort to preserve King Mountain.

"He was our champion at the county in the 1980s," Moller said.

Marin County had the property appraised and offered to purchase all 292 acres at the appraised price. When this offer was rejected by the owner, the two parties entered into private negotiations.

The $3.4 million raised to purchase 131 acres of the property came in equal parts from the Marin Community Foundation, the Marin Open Space Trust and a special assessment district of Larkspur residents established through the association.

"The people of Larkspur literally taxed themselves to help with the purchase price," Moller said.

When the transaction was nearing completion in 1989, the property owner, Tiscornia Estate Co., balked at the last moment at allowing the loop trail easement. It relented, however, after the association threatened to withdraw its support for the transaction unless it got the trail.

Nevertheless, the association was never content with the deal.

"Our intent the entire time was to get the entire mountain," said Patrick Seidler, a co-founder.

The association has continually monitored the ownership of the property, which changed hands at least five times over the years.

Dickenson said the county later upzoned the property to one residence per 53 acres. It was under this zoning that one former owner of the property, Herbert Boyer, co-founder of Genentech, secured approval to build a 5,000-square-foot main house, a 5,000-square-foot guest house and a 1,500-square-foot caretaker's house at the summit.

Dickenson said the meadow on the mountain didn't exist originally and might have been cleared for a barn and planned vineyard. However, Boyer never followed through on the project.

In 2021, another owner of the property tried to auction off the 161-acre parcel, but garnered only modest interest.

"It would have to be someone willing to invest tens of millions of dollars in improvements," Dickenson said.

Somers said the Shelby Cullom Davis Charitable Fund proposed the gift at the prompting of one of its board members, a Marin resident who prefers not to be named.

"This particular board member lives in Mill Valley and really has fallen in love with hiking on King Mountain," Somers said. "I guess at some point he realized that King Mountain was not actually public property. "

The amount the fund is paying for the property has not been disclosed.

"This celebration reflects 41 years of community persistence to preserve King Mountain's majestic backdrop to Larkspur and the Ross Valley," Seidler said.

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