A hilltop visible from the Richmond-San Rafael Bridge but fenced off from the public for decades will become a permanent open space preserve after the Marin County Open Space District Board of Directors voted Tuesday, July 14, to accept a 161-acre land donation and $2 million stewardship fund.

The acquisition nearly triples the existing King Mountain Open Space Preserve, expanding it from 108 acres to roughly 269 acres. More immediately for hikers: the 32-acre summit, which offers 360-degree views of Mount Tamalpais, the Tiburon Peninsula, and San Pablo Bay, will open to the public for the first time. A padlocked iron gate currently blocks the fire road leading from the existing 3.5-mile loop trail to the top.

"This really came out of nowhere. Nobody was expecting this. It's been a frenzy to facilitate this transaction," Marin County Parks Director Chris Chamberlain told the San Francisco Chronicle.

The deal cost taxpayers nothing. The Shelby Cullom Davis Charitable Fund, a Delaware-based philanthropy, cold-emailed Marin Open Space Trust (MOST) Chair Bill Long roughly six months ago asking about purchasing and donating the property. Long, a longtime Novato resident who helped create the Open Space District in 1972, said he had never heard of the foundation before.

MOST signed a purchase agreement with the prior owner, Omega Three Trust, in April 2026. The property had been listed at $19 million; the final sale price was not disclosed.

A previous owner had obtained approvals in the 1990s to build a 27,500-square-foot estate on the summit. The residence was never constructed, but the entitlements remained, making luxury development a real possibility until the donation.

The $2 million stewardship fund will cover at least a decade of maintenance, according to the county news release. First-year spending of $400,000 includes removal of invasive French broom, demolition of fencing and a guardhouse, installation of signage, and placement of two picnic tables near the summit, according to a staff report by Carl Somers, the district's chief of planning and real property.

The nonprofit MOST brokered the transaction. Long said the acquisition "fills a gap between three discontinuous parcels of public land" and achieves the goal of securing the entire mountain for open space without using public funds.

David Moller, president of the King Mountain Open Space Association, a community group that has pushed for conservation of the summit for decades, told the Chronicle that prior attempts to persuade former owners to sell never gained traction.

Local hikers are already celebrating. In a post on Instagram, the Larkspur Community Foundation wrote: "King Mountain preserved for all! ... See you on the top of King Mountain!"

Supervisor Brian Colbert, who represents Central Marin including King Mountain, called the donation "an important investment in both conservation and community access" in the county's news release.

Under the donation agreement, MOST must transfer the property to the Open Space District by September 8, 2026. No official public opening date has been announced. According to the Chronicle, access could begin as soon as the gate is unlocked and fencing removed.