Yellowstone River

The Yellowstone River is a river in the northwestern part of the United States.  It is a tributary of the Missouri River and flows through the states of Wyoming, Montana, and North Dakota. It also flows through Yellowstone National Park and feeds Yellowstone Lake. 

The Yellowstone River was first explored in 1806 by William Clark during the return trip of the Lewis and Clark Expedition.
 Other websites 

Fish and Wildlife Service: Upper Missouri River and Yellowstone 
USGS Site: Lewis and Clark Expedition 
State of Montana: Yellowstone River Physical Features Inventory 
State of Montana: Lower Yellowstone Corridor Physical Features Inventory 

Category:Rivers of Montana
Category:Rivers of North Dakota
Category:Rivers of Wyoming