Calistoga Guide: Geothermal Hot Springs, Volcanic Ash Mud Baths & California's Old Faithful Geyser

At the northern tip of Napa Valley beneath the 1,323-metre volcanic peak of Mount Saint Helena sits Calistoga, the most relaxed, unpretentious town in the valley. Founded in 1859 by pioneer Samuel Brannan (who wanted to create the 'Saratoga of California', accidentally slurred the two words together at a dinner party as 'Calistoga of Sarafornia', and the name stuck), the town sits directly atop an underground geothermal aquifer heated by volcanic magma to over 100°C (212°F).

1. Soaking in Calistoga's Geothermal Mineral Pools & Volcanic Ash Mud Baths

Unlike chlorine hotel pools, Calistoga's spa resorts pipe pure, mineral-rich underground geothermal geyser water directly into outdoor soaking pools ranging from 32°C to 40°C (90°F to 104°F). Since the 1860s Calistoga has also been famous for its Volcanic Ash Mud Baths, where you float weightlessly in warm 39°C local volcanic ash mixed with organic peat moss and mineral water, followed by a mineral whirlpool soak and eucalyptus steam room. Top places to book a day spa treatment or overnight stay:

• Dr. Wilkinson's Backyard Resort & Mineral Springs (1507 Lincoln Ave): opened in 1952 by 'Doc' Wilkinson as the pioneer of the modern Calistoga Mud Bath, renovated in retro mid-century style with three geothermal mineral pools.
• Indian Springs Calistoga (1712 Lincoln Ave): home to an Olympic-sized 1913 geothermal pool fed by four active on-site geysers, volcanic-ash mud baths and the patio of Sam's Social Club.
• Roman Spa Hot Springs Resort, Calistoga Motor Lodge & Solage / Four Seasons: ranging from retro motel value to five-star vineyard luxury.

2. Walk Lincoln Avenue: 'Tank Garage Winery' & 'Old Faithful Geyser'

1. Tank Garage Winery (1020 Foothill Blvd at Lincoln Ave): one of the most laid-back tasting rooms in Napa Valley, housed inside an authentic 1930s Texaco Lubritorium service station complete with vintage petrol pumps, neon signs and a back-room speakeasy pouring small-batch blends.
2. The Old Faithful Geyser of California (1299 Tubbs Lane): a geothermal geyser that shoots 175°C underground water 18 to 25 metres into the air every 20 to 40 minutes, surrounded by picnic grounds and friendly Tennessee Fainting Goats, llamas and Jacob four-horned sheep.