It rises in the high Cascades, issuing from Maidu Lake at elevation of in the Mount Thielsen Wilderness, along the Douglas-Klamath county line approximately east of Roseburg. It follows a serpentine course down from the Cascades, westward along the southern side of the Calapooya Mountains. Its upper course passes through the Umpqua National Forest, past Toketee Falls and Steamboat, where it receives Steamboat Creek from the north. It receives the Little River from the south at Glide (the confluence is known as the Colliding Rivers) and joins the South Umpqua from the east approximately northwest of Roseburg to form the Umpqua.