Robert Louis Stevenson State Park Professional Guide
Detailed Trail Description from our Guidebook
"Mount St. Helena is the Bay Area’s highest publicly accessible (by trail) peak, topping out at 4,304 feet. This trek begins uphill on a short, eroded trail, then continues to the summit on a long, sinuous, well-graded fire road. There’s very little challenge here, just a steady climb to the top, where views unfold, spanning the distance from the San Francisco skyline to Mount Lassen (on a clear day)."