Geothermal mineral springs—often called hot springs—are a fabulous wellness attribute of Sonoma County.
Hot mineral springs, which exist around the world, are produced when geothermally-heated and mineralized groundwater emerges from the earth to form pools of water ranging from warmish to scalding. Most people enjoy springs that hit a sweet spot somewhere between warm and hot—the point at which water relaxes mind and body, soothes aching joints, and introduces a feeling of bliss. It’s no surprise that, throughout history, such springs have attracted visitors eager to “take the waters.”
For centuries, Sonoma County’s geothermal springs attracted Native Americans from the surrounding region and well beyond; many tribes considered certain springs to be sacred, and they would travel for days to immerse themselves in the waters. In the late 1800s and well into the 19th century, many county hot springs became wildly popular vacation resorts in which people stayed for weeks at a time. The Geysers area in Northern Sonoma County, Napa County, and Lake County represents the largest geothermal field in the world.
Today, you can still enjoy three of Sonoma County’s most legendary hot springs: Boyes Hot Springs, Morton’s Hot Springs, and Agua Caliente:
Boyes Hot Springs
The thermal waters of Boyes Hot Springs come in a luxurious setting at the Fairmont Sonoma Mission Inn & Spa. Originally built in 1927 in the style of California’s early missions, the property was renovated in the late 20th century. Shortly thereafter, a new thermal mineral water source was discovered more than 1, 000 feet below the hotel.
The waters of Boyes Hot Springs can be enjoyed in the pools and Jacuzzi at the Inn’s Willow Stream Spa. Water temperature varies from pool to pool. The Watsu pool is kept at body temperature; the indoor Jacuzzi is somewhat warmer; and the spa’s main pool hovers around 85°. A spa treatment isn’t required. Bathhouse access for hotel guests is $29 (the fee is waived if you have a same-day spa treatment); non-hotel or “day guests” without spa treatments are charged $89. Open year-round.
The Fairmont Sonoma Mission Inn & Spa, 100 Boyes Blvd, Sonoma, 707-938-9000
When you dip into a pool at the Sonoma Aquatic Club in Agua Caliente, you join a tradition that dates back countless centuries: hanging out, for recreational or curative purposes, in these soothing thermal mineral waters. The hot springs here were reputed to be so curative that distant tribes traveled days to bathe in them.
You’ll find three pools: an Olympic-sized outdoor pool, with 25-yard and 50-meter courses, as well as lap swimming and recreational swimming; an indoor 90° pool; and an outdoor covered 102° Jacuzzi with lots of jets at many levels. All water comes directly from the natural hot springs below ground. There’s also a workout room with treadmills, elliptical machines, stationary bikes, a Stairmaster, and weights. In-pool classes include water yoga, aqua aerobics, and an adult swim clinic. The Aquatic Club offers individual and family memberships. Visitors can arrange a one-day visit for $20.
Morton’s Warm Springs
The 22 acres of Morton's Warm Springs Resort, nestled into a bucolic setting of forested hills and a lively creek, is located about four miles from Glen Ellen’s village center. The property’s geo-thermal mineral springs, once sacred to the local Wappo Indians, remain accessible today in three mineral spring pools; water averages between 82-84°, and pool depth ranges from 4.5 to 9 feet. The pool area is furnished with comfortable chaises, lifeguards are on duty, and you can safely store your possessions in shower room lockers.
While there you can also enjoy Morton’s hiking and biking trails, which wind into the surrounding hills, along with basketball and volleyball courts, a baseball field, croquet, ping pong, horseshoe pits, a kids’ playground, and plenty of picnic and BBQ sites. Morton’s is open each year from May through September (check the website for days and times).