How you say it, and where it comes from
Coachella (pronounced koe-CHEL-uh) is the name of a city as well as a valley in southern California. The Coachella Valley rests between Salton Sea and the San Bernardino Mountains in the Colorado Desert, and is home to the city of Coachella as well as other cities and towns, including several resort towns, the most famous of which is Palm Springs. The valley is increasingly famous for the Coachella Valley Music and Arts Festival, which takes place annually in the city of Indio—and triggers an annual surge in dictionary lookups for Coachella.
Although comedian Jimmy Kimmel's "Lie Witness News" reported in 2013 that Coachella comes from an American Indian word for "dumb white guy," that assertion was, unsurprisingly, a lie. Coachella comes from a misspelling of the valley's old name, Conchilla, from a Spanish word meaning "little shell" that referenced the fossil shells found in the area.
The valley was also called Cahuilla for a time, for the Cahuilla Indians who lived there.