The Plains of Leon are bounded on the west by the Paloma Valley, the southeastern Temescal Mountains and the valley of Warm Springs Creek after it drops below the level of the tablelands of the plains. On the north by Menifee Valley and the Domenigoni Mountains, on the south it extends to include French Valley, Auld Valley and the tablelands between them. It is bounded on the south by Tucalota Creek (originally Alamos Creek), and the level land west of it to Warm Springs Creek and northeast of Murrieta Hot Springs. To the east it was originally bounded by the eastern Diamond Valley, Rawson Mountains, Bachelor Mountain, Black Mountain, and Tucalota Hills. However, now Diamond Valley is bounded on the east by the West Dam of the Diamond Valley Lake. Auld Valley is now bounded to the east by Skinner Reservoir south of Bachelor Mountain on Tucalota Creek.