[1] Prior to annexation, Murrieta Hot Springs was a Census-designated place of Riverside County, California.

[3] The neighborhood grew up around a hot springs spa that was developed as a resort starting in the 1880s and became a college campus and conference center in the 1990s.

[6] The springs had been used for a Chinese laundry[6] before the Temecula Land & Water Company developed the site in 1884 with a hotel and a bathhouse.

Fritz Guenther, a German who had settled in Los Angeles, bought the tract in 1902, built two new hotels and a new bathhouse, and later added cottages.

[6] In January 1970, Murrieta Hot Springs and the surrounding area, some 500 acres, was sold to Irvin Kahn, a San Diego attorney and real estate developer who had visited the spa as a child.

Kahn purchased additional land and with Teamsters Union lawyer Morris Shenker as co-owner, constructed a mobile home park above the spa and held golf and tennis tournaments.