It rises in the Wallowas in the Eagle Cap Wilderness of the Wallowa-Whitman National Forest, just south of the Wallowa-Union border approximately southeast of La Grande at Blue Lake. It flows generally northwest through the mountains along the Wallowa-Union county line. It joins the Wallowa from the south at the community of Minam near Oregon Route 82. Its headwaters include springs stemming from outflow from Minam Lake, also the source of the Lostine River.