Big Rock Ridge and Loma Alta are the 2nd and 4th highest points in the county at 1,895 and 1,592 ft respectively. Combined with Green Hill, the highest point on San Geronimo Ridge (1,418 ft), this trio of peaks afford some of the most serene, sweeping views in the bay area.

Meet a ranger for a guided climb to the top of San Geronimo Ridge in the Gary Giacomini Preserve. We'll ascend through a redwood grove in the valley and visit a pygmy Sargent Cypress forest on the ridge top, learning about ecology and history on the way. Be prepared for a sustained climb, approximately 900 ft elevation gain and 4 miles. Wear sturdy walking shoes/boots, sunscreen, and a hat. Bring plenty of water, snacks, and a camera.