The Little Naches River begins in several forks near Naches Pass and boundaries of Yakima County, Kittitas County, Pierce County, and King County. The Yakima-Kittitas county line follows the upper Little Naches and Naches rivers, but most of the Naches River basin is in Yakima County. Pierce and King counties are bounded by the water divide between Puget Sound and the Columbia River. Thus the tributaries of the Naches River reach up to, but not across, the Pierce and King county lines.