Geothermal Mineral Springs at Sonoma Mission Inn & Spa

Geothermal Springs of Sonoma Mission Inn & Spa


Our spa pools and hot tub are open year-round for guests 18 years and older. Food and beverage pool service is offered seasonally in the warm weather months.

Geothermal mineral springs-often called hot springs-are a fabulous wellness attribute of Sonoma County. The Geysers area in Northern Sonoma County represents part of the largest geothermal field in the world. 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.

The thermal waters of Boyes Hot Springs come in a luxurious setting at Fairmont Sonoma Mission Inn & Spa. Originally built in 1927 in the style of California's early missions, our 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 hot tub at the Inn's Willow Stream Spa. Water temperature varies from pool to pool. The Watsu pool is kept at body temperature; the indoor spa is somewhat warmer; and the spa's main pool hovers around 85° (but the main pool is open to hotel guests only).


Written by Sonoma County Insider Suzie Rodriguez

"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."