Mount Tamalpais is Marin County’s dominant mountain and a widely recognized symbol of the county, rising just north of San Francisco as the highest peak in the Marin Hills of the Northern California Coast Ranges. First recorded in 1845, its name comes from the Coast Miwok támal pájiṣ, meaning “west hill.” Much of the mountain is protected within state, local, and federal public lands, preserving extensive open space. Shaped by tectonic activity near the San Andreas Fault zone, it includes distinctive serpentine soils that support endemic plants. Its sharp variations in climate, rainfall, and terrain sustain exceptional ecological diversity, from redwood forest to chaparral and native grasslands.