The Gila River Valley is a multi-sectioned valley of the Gila River, located primarily in Arizona. The Gila River forms in western New Mexico and flows west across southeastern, south-central, and southwestern Arizona; it changes directions as it progresses across the state, and defines specific areas and valleys. The central portion of the river flows through the southern Phoenix valley region (the Salt River Valley joins the Gila River Valley in this area), and the final sections in southwestern Arizona form smaller, irrigated valleys, such as Dome Valley, Mohawk Valley, and Hyder Valley.