An undeveloped mountaintop at the heart of Marin County — just east of Mount Tamalpais — that had been closed to the public for decades is now open to hikers.
The summit of King Mountain, a redwood- and oak-studded peak near downtown Larkspur surrounded by an open space preserve, had been privately owned and off-limits for decades. For a time, it was slated to be the site of a 27,500-square-foot residential compound.
Then in July, with a sizable donation from a Delaware-based philanthropic foundation, Marin County acquired the 161-acre property…