Yellowstone River

Yellowstone River
Yellowstone Falls in the Grand Canyon of the Yellowstone
Country	United States
States	Wyoming, Montana, North Dakota
Tributaries
- left	Gardner River, Shields River
- right	Lamar River, Boulder River, Stillwater River, Big Horn River, Tongue River, Powder River
Source	Confluence of North and South Forks
- location	Absaroka Range, Wyoming
- coordinates	43°59′18″N 109°55′45″W / 43.98833°N 109.92917°W / 43.98833; -109.92917
Mouth	Missouri River
- location	McKenzie County, near Buford, North Dakota
- coordinates	47°58′42″N 103°58′56″W / 47.97833°N 103.98222°W / 47.97833; -103.98222Coordinates: 47°58′42″N 103°58′56″W / 47.97833°N 103.98222°W / 47.97833; -103.98222
Length	692 mi (1,114 km)
Basin	70,000 sq mi (181,299 km2)
Discharge	for Sidney, MT
- average	13,773 cu ft/s (390 m3/s)
- max	159,000 cu ft/s (4,502 m3/s)
- min	3,108 cu ft/s (88 m3/s)
Map of the Yellowstone River watershed

The Yellowstone River is a tributary of the Missouri River, approximately 692 miles (1,114 km) long, in the western United States. Considered the principal tributary of the upper Missouri, the river and its tributaries drain a wide area stretching from the Rocky Mountains in the vicinity of the Yellowstone National Park across the mountains and high plains of southern Montana and northern Wyoming.

The Yellowstone River Watershed is a river basin located in North Dakota, Wyoming, and Montana. The Yellowstone Basin Watershed contains a system of rivers, including the Yellowstone River, and four tributary basins: the Clarks Fork Yellowstone, Wind River and Bighorn River, Tongue River, and Powder River. These rivers form tributaries to the Missouri River. The mainstem of the Yellowstone River is more than 1,130 kilometres (700 mi) long. At the headwaters, elevations exceed 3,900 metres (12,800 ft) above sea level and descends to 564 metres (1,850 ft) at the confluence with the Missouri River in North Dakota. The watershed spans 34,167 square miles. The area contains many lakes, including Yellowstone Lake. There are no storage dams located on the mainstem of the Yellowstone River. However, the watershed contains five major reservoirs: Bull Lake, Boyson, Buffalo, Bighorn, Tongue River, and Lake De Smet reservoirs.