Metallica's Lars Ulrich once planned a $40 million mansion on this California ridge; now 161 acres are being preserved as public open space

For years, a ridgeline in Marin County carried the possibility of becoming the private retreat of Metallica drummer Lars Ulrich. The 161-acre property on King Mountain was once slated for a sprawling residence, and Ulrich later pursued plans for an architect-designed compound of his own, complete with space for music archives, a recording studio and a workroom. Construction even reached the foundation before the project was abandoned. The mountaintop then remained privately held, despite sitting alongside public open space and offering wide views across Mount Tamalpais, Tiburon and San Pablo Bay.Now its future is changing in a very different direction. The land has been acquired through a conservation deal and is being transferred to Marin County, protecting it from residential development. Once the necessary work is completed, part of the previously inaccessible summit is expected to open to the public, turning a site once intended for a private mansion into protected open space.Ulrich's ambitious plans for the King Mountain ridgeUlrich's connection to the property dates back to the early 2000s, when the Metallica drummer began developing plans for a substantial compound on the King Mountain ridge.The proposed house was designed by architect Stanley Saitowitz. It was far removed from a conventional suburban mansion. Plans showed a modern, low-profile structure built around the hillside, with large areas of glass and separate spaces intended for Ulrich's work and music collection.The design included a music archive, recording studio and work room. Construction actually got as far as the foundation before the project was abandoned.The property was subsequently placed on the market. At one stage, the asking price was around $40 million, although later listings were considerably lower. Despite the property's development potential, no private estate ultimately appeared on the ridge.King Mountain's summit stayed private for decadesThe 161-acre property had been the subject of planning battles and conservation efforts for decades. In the 1990s, a previous owner secured approval for a residential compound of roughly 27,500 square feet. The plans demonstrated just how different the summit might have looked if the development had gone ahead.The approvals remained in place even as ownership changed.Meanwhile, Marin County had been building its own patchwork of protected land around the mountain. Existing portions of the King Mountain Open Space Preserve were acquired in 1989 and 1990, while the county also held scenic and trail easements across parts of the privately owned property. The result was a public trail system that effectively surrounded land people could not enter. The summit itself remained the missing piece.A conservation deal finally secured King Mountain's summitThe breakthrough came in 2026, when the Marin Open Space Trust negotiated to buy the 161-acre property with funding from the Shelby Cullom Davis Charitable Fund.The trust then arranged for the land to be donated to the Marin County Open Space District. On July 14, the district board approved the agreements, clearing the way for the property to become part of the King Mountain Open Space Preserve.The transaction will expand the preserve from 108 acres to approximately 269 acres. More importantly for visitors, about 32 acres around the summit that had been off limits will eventually become accessible to the public.The $2 million plan to prepare King Mountain for public useThe new arrangement removes the possibility of the summit becoming another large private residential estate.That matters because the high ground is not simply a viewpoint. The summit contains native prairie and hardwood forest, along with broad views across the surrounding landscape. From the top, visitors can see Mount Tamalpais, the Tiburon Peninsula and San Pablo Bay.The conservation purchase also comes with money for looking after the property. The Davis charitable fund is providing a $2 million stewardship fund to support management and public-access work for at least a decade.Some of the initial work is fairly practical. Plans include removing sections of fencing, taking down a guardhouse, tackling invasive vegetation and installing signs. Picnic tables are also planned near the summit.The mountain therefore will not simply change ownership and immediately look different. Some of the physical traces of its private past have to be removed first.From private compound to public open spaceThere is a strange symmetry to the property's history. The mountaintop was once seen as the site for a large estate. Ulrich's plans took that idea further, with a purpose-built home designed around music, work and the views from the ridge. A foundation was poured, but the house was never completed.Years later, the same 161 acres are being secured for a purpose that requires no mansion at all.The county's existing preserve will stretch across the mountain, connecting previously separated pieces of public land. The summit, once the part people could see but not reach, will become the part they can finally walk to.For King Mountain, the most significant change is not the end of an old building proposal. It is what replaces it: a protected ridgeline, native habitat and a public viewpoint where a private compound might once have stood.Catch the latest World News and Live updates. Download the TOI app.