Come learn about the geology of northern Napa County. We will be hiking up to an overlook facing south toward Calistoga and the Bay. Learn about the volcanism of the region, the source of the hot springs, and the quicksilver mining of northern Napa County.  We will meet at the Robert Louis Stevenson State Park Trailhead, approximately 7.5 miles north of the intersection of Silverado Trail and Highway 29.

Difficulty: moderate

Length: 3mi

Total Ascent: 778 ft




  • Occurred Saturday, February 16th, 2019 @ 10:00 am – 12:00 pm


Robert Louis Stevenson

4625 Lake County Hwy
Calistoga, CA 94515

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