The story of The Fairmont Sonoma Mission Inn & Spa dates back to the Native Americans who were the first to discover the natural underground hot mineral waters. This site was considered a sacred healing ground and their 'sweathouse' stood near the spring for generations. In 1840, Dr. T.M. Leavenworth, an eccentric San Francisco physician, was the first to commercially develop the hot springs. In 1895, Captain H.E. Boyes, an enterprising young Englishman, acquired the property and struck 112 degree water at 70 feet while drilling a well. Within five years, he had built the Boyes Hot Springs Hotel on the site of the current property.  Soon, well-to-do San Franciscans were arriving by boat and train to 'take the waters' at the finest hot mineral water resort in California. In 1923, a disastrous fire destroyed the hotel and most of Boyes Hot Springs. However, in 1927, the current Inn rose from the ashes as an architecturally accurate replica of a California Mission. Once again, the Inn was filled with guests, and this unique hot springs resort was hailed as one of the finest in all of Northern California.

During the Great Depression, which began with the fall of the stock market in 1929, the resort was plummeted into receivership. It remained dark until 1933, when it was purchased by Grass Valley hotelier Emily Long and restored to prosperity. During World War II the hotel fell under the control of the Navy. It became an 'R&R' site for sailors and marines until 1945. Various incarnations followed, including the use of the Inn by famous sports teams as a training headquarters. During that period, The Big 3 established itself as a gathering place for locals and hotel guests alike. The longest running continuously-operated restaurant in Sonoma Valley, The Big 3 anchors the corner of Highway 12 and Boyes Boulevard at the entrance to the Inn.

In 1980, major renovation returned the Inn to its 1920's grandeur, and the Spa, added in 1981, attracted visitors from around the globe. Since then, the most recent additions and renovations, began in 1999 and completed in 2000, include the expansion of the Spa, to its 40,000 sq.ft. indoor and outdoor space, beautifully appointed, lush landscaping making this a true European Spa.

Sixty new suites, landscaping, the addition of a parking garage, and function space, make The Fairmont hot springs hotel – The Fairmont Sonoma Mission Inn & Spa a truly unique Sonoma resort for the 21st century.