The Whitlock Valley is a small valley in southeast Arizona, USA, lying between three mountain ranges. The valley lies on the south perimeter region of the White Mountains in eastern Arizona, and lies south of the west-flowing Gila River, and the region transitions south into Cochise County and three large valleys, with some scattered dry lakes. The valley is endorheic, with a small dry lake called Parks Lake, and merges southwest into the north of the San Simon Valley, where the San Simon River has its origins in the flatlands, and surrounding perimeter mountains. The valley was named after Captain James H.