Adelaide Peak is an unofficially named summit in the southern Temescal Mountains that rises 2,279 feet. It is composed of Cretaceous granitic rock from the Peninsular Ranges Batholith. The peak also marks a local drainage divide: water from its southern slopes runs into an unnamed tributary arroyo of Murrieta Creek within the Santa Margarita River system, while runoff from its northern slopes enters an unnamed tributary of Salt Creek and ultimately flows toward the San Jacinto River.