The Shields River is a tributary of the Yellowstone River

Yellowstone River

The Yellowstone River is a tributary of the Missouri River, approximately 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...

, approximately 50 mi (80 km) long, in Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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It rises in the Gallatin National Forest

Gallatin National Forest

Founded in 1899, Gallatin National Forest is located in south central Montana, United States. The forest comprises 2.1 million acres and has portions of both the Absaroka-Beartooth and Lee Metcalf Wilderness areas within its boundaries...

 in the Crazy Mountains

Crazy Mountains

The Crazy Mountains, often called the Crazies, are a mountain range in the northern Rocky Mountains in the U.S. state of Montana.-Geography:...

 in northern Park County

Park County, Montana

Park Counties in Montana and Wyoming are among the very few pairs of counties in the United States with the same name to border each other across state lines.-National protected areas:* Custer National Forest * Gallatin National Forest...

. It flows west, then south, between the Bridger Range to the west and the Crazy Mountains to the east, past Wilsall

Wilsall, Montana

Wilsall is a census-designated place in Park County, Montana, United States. The population was 237 at the 2000 census.-Geography:Wilsall is located at ....

 and Clyde Park

Clyde Park, Montana

Clyde Park is a town in Park County, Montana, United States. The population was 310 at the 2000 census.-Geography:Clyde Park is located at ....

. It joins the Yellowstone approximately 10 mi (16 km) northeast of Livingston

Livingston, Montana

-Geography:Livingston is located at , at an altitude of 4.501 feet .According to the United States Census Bureau, the city has a total area of , of which, of it is land and 0.38% is waters.-Climate:-Demographics:...

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