Yellowstone River Drainage from Chittenden Bridge to the Lamar Confluence Professional Review and Guide
"The Yellowstone River flows northward 15 miles through its spectacular Grand Canyon, downstream from Chittenden Bridge. People often mistakenly assume that the river and the park take their name from the predominant yellow rock of the canyon walls. It is more likely that the aboriginal name of the stream was the Elk River. It comes to us as the Yellowstone because Le Roche Juene, “yellow stone” in French, is the name that Lewis and Clark had for the river. They got this name from French-Canadian explorers who had ascended the Missouri as far as the Mandan villages in what is now central North Dakota.
The Mandan, in turn, almost certainly were referring to the yellowish rim rocks of the lower river near present-day Billings, Montana. The junction of the Yellowstone with the Lamar marks the end of the Grand Canyon and this section of the river. The Lamar is the largest tributary drainage of the Yellowstone River within the park. It and its tributaries comprise a major portion of this section of the guide. Tower and Broad Creeks, plus several other less substantial tributaries, also join the Yellowstone in this reach. This eTrail contains information on Seven Mile Hole, Cascade Lake, Ribbon Lake, Broad Creek, Yellowstone River Drainage (Broad Creek to Lamar River), and Tower Creek."