The Apache Wars discouraged development of the area until the 1880s when the springs and the adjacent land were purchased by Frank Murphy for the construction of a health resort. The resort was completed in 1896 by the brother of the Arizona Governor Oakes Murphy, and the newly renamed "Castle Hot Springs" was heavily advertised to potential clients. During the resort's heyday in the 1920s it was visited by celebrities such as Zane Grey, as well as famous families such as the Rockefellers.

The resort was used by the United States military as a rehabilitation center from 1943 to 1944 to treat injured veterans of World War II. Future president John F. Kennedy spent three months at the resort during this period to recover from his wounds suffered during the sinking of his ship, PT-109.

The resort continued to be commercially operated until the main building was heavily damaged in a fire in 1976.^[1] The resort still comprises its swimming pool, administrative building and guest house along with the springs, which produce 180,000 gallons of hot water per day.^[2] The resort became a stop on the short-line Arizona and California Railroad in the 1990s.

The property was sold in March 2014 for $1.95 million.^[3] In March 2018, the resort announced a restoration was underway with plans for reopening in October of that year.^[4] The new owners have extensively remodeled and added to the property, adding 12 spring bungalows - with hot spring fed tubs, and 17 sky-view cabins. The resort reopened to visitors in February 2019.^[5]

Castle Hot Springs Resort was the subject of a 1994 documentary film by Mike Smith and a fellow student.^[6]

• Sasco, Arizona
• Treasures from American Film Archives: Treasures 5: The West, 1898–1938 (2011) (disc 3)
• Santa Monica Army Air Forces Redistribution Center

• Reagor, Catherine (March 18, 2014), "Historic Castle Hot Springs resort in Arizona sells for $1.95 million", Arizona Republic
• Rodriguez, Nadine Arroyo (February 21, 2014), A Piece Of Arizona History Is For Sale In Castle Hot Springs, Phoenix, Arizona: KJZZ (National Public Radio)
• Reagor, Catherine (January 21, 2014), "Castle Hot Springs resort to be auctioned", Arizona Republic
• Buchholz, Jan (March 13, 2012), "Historic Castle Hot Springs back on market for $5.7 million", Phoenix Business Journal
• Sheridan, M.F.; Satkin, R.L.; Wohletz, K.H. (1980), "Geothermal resource evaluation of Castle Hot Springs, Arizona", Document Repository, Repository.azgs.az.gov, Arizona Geological Survey, State of Arizona
• Olson, Carl; Whitley, Kim, "Castle Hot Springs", Arizona Heritage Waters, AZHeritageWaters.NAU.edu, Northern Arizona University, retrieved July 16, 2014
• Castle Hot Springs, Arizona (PDF), Chicago and New York: Rogers & Company, 1907, L9791 C353 Pam. 2 (University of Arizona)
• Castle Hot Springs Collection, 1951–1982 (PDF), Arizona Historical Foundation
• "Virtual Browsing Book: Buildings-Hotels (7)", Library and Archives: Photographs, Sharlot Hall Museum, Sharlot.org

• Castle Hot Springs – ghosttowns.com
• Castle Hot Springs – Jewel of the Bradshaws! (December 31, 2011), from SonoranTreeSvc.com
• Castle Hot Springs, at DailyJFK.com
• Castle Hot Springs Resort New Castle Hot Springs website for rebuilt resort

33°58′58″N 112°21′43″W / 33.98275°N 112.3619°W / 33.98275; -112.3619