Calistoga Geyser (Napa Valley, California, USA) 2
(vintage photo by Willard Culver) (public signage at Calistoga Geyser visitor center)
Calistoga Geyser is an artificial feature - it is an erupting geothermal well in California's Napa Valley. It goes by many names: Calistoga Geyser, Old Faithful Geyser of California, Little Old Faithful Geyser, Mt. St. Helena Geyser.
The original well was drilled 70 meters deep in the late 1800s. It erupts from a well casing. Before California's 1989 Loma Prieta Earthquake ("World Series Earthquake"), Calistoga Geyser changed its eruption frequency - a famous precursor event.
Despite it being artificial, it is part of the naturally-occurring Calistoga Geothermal Field. "The Palisades" are visible to the east of this site, above the northwestern end of the Napa Valley, and consist of Tertiary-aged Sonoma Volcanics. Mt. St. Helena, also composed of Sonoma Volcanics, is visible to the north of here.
Locality: northwestern side of Tubbs Lane, northwestern side of town of Calistoga, northwestern end of the Napa Valley, west-central California, USA (38° 35' 49.12" North latitude, 122° 36' 07.69" West longitude)