From Wikipedia, the free encyclopedia.
The Yellowstone River is a tributary of the Missouri in the western United States.
It rises in Yellowstone Lake in Yellowstone National Park in northwestern Wyoming, and forms the Grand Canyon of the Yellowstone within the confines of the park. It flows northward into Montana through the Absaroka Range and emerges from the mountains near the town of Livingston, where it turns eastward, flowing across the northern Great Plains past the city of Billings.
East of Billings, it is joined by the Bighorn River. Further downriver, it is joined by the Tongue near the town of Miles City, and then by the Powder in eastern Montana. It joins the Missouri in extreme western North Dakota, upriver from the town of Williston. At the confluence with the Missouri, the Yellowstone is actually the larger river.
The river was explored in 1806 by William Clark, during the return voyage of the Lewis and Clark Expedition. In its upper reaches, within Yellowstone Park and the mountains of Montana, it is a popular destination for fly fishing.
See: List of Wyoming rivers, List of Montana rivers
