Rainbow Valley is a small

valley A valley is an elongated low area often running between Hill, hills or Mountain, mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers ...

Riverside County Riverside County is a county located in the southern portion of the U.S. state of California. As of the 2020 census, the population was 2,418,185, making it the fourth-most populous county in California and the 10th-most populous in the Unit ...

and

San Diego County San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the fi ...

in the U.S. state of

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. It is the site of the settlement named

Rainbow A rainbow is a meteorological phenomenon that is caused by reflection, refraction and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky. It takes the form of a multicoloured circular arc. Rainbows c ...

. The area was previously known as Vallecitos ("little valley") and was renamed Rainbow Valley in the late 1880s after James Peebles Marshall Rainbow, who bought a homestead there.A Man Called Rainbow by Vincent Nicholas Rossi, San Diego History Seeker; Exploring San Diego History, January 11, 2016
from sandiegohistoryseeker.com accessed April 15, 2016.

References

Valleys of San Diego County, California Valleys of Riverside County, California {{SanDiegoCountyCA-geo-stub