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Mount Saint Helena

Mountain on Stevenson Memorial Trail in Coast Ranges near Middletown, CA

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Mount Saint Helena (Wappo: Kanamota, "Human Mountain") is a peak in the Mayacamas Mountains with flanks in Napa, Sonoma, and Lake counties of California. Composed of uplifted 2.4-million-year-old volcanic rocks from the Clear Lake Volcanic Field, it is one of the few mountains in the San Francisco Bay Area to receive any snowfall during the winter. The mountain has five peaks, arranged in a rough "M" shape. Its highest point, North Peak, is in Sonoma County. The second-tallest, immediately east of the main summit, is the highest point in Napa County. The headwaters of the Napa River are on the southeast slope of Mount Saint Helena.