Belt Creek is a tributary, approximately 80 mi (129 km) long, of the Missouri River

Missouri River

The Missouri River flows through the central United States, and is a tributary of the Mississippi River. It is the longest river in North America and drains the third largest area, though only the thirteenth largest by discharge. The Missouri's watershed encompasses most of the American Great...

 in western 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 originates in the Lewis and Clark National Forest

Lewis and Clark National Forest

Lewis and Clark National Forest is located in west central Montana, United States. Spanning , the forest is managed as two separate zones. The eastern sections, under the Jefferson Division, is a mixture of grass and shrublands dotted with "island" pockets of forested areas. Here, cattle leases to...

 north of Big Baldy Mountain, in the Little Belt Mountains

Little Belt Mountains

The Little Belt Mountains are a section of the Rocky Mountains in the U.S. state of Montana. Situated mainly in the Lewis and Clark National Forest, the mountains are used for logging and recreation for the residents of Great Falls, Montana...

 in western Judith Basin County

Judith Basin County, Montana

-Demographics:As of the census of 2000, there were 2,329 people, 951 households, and 661 families residing in the county. The population density was -Demographics:...

. It flows northwest through mountainous canyon

Canyon

A canyon or gorge is a deep ravine between cliffs often carved from the landscape by a river. Rivers have a natural tendency to reach a baseline elevation, which is the same elevation as the body of water it will eventually drain into. This forms a canyon. Most canyons were formed by a process of...

s (Limestone Canyon) past Monarch

Monarch, Montana

Monarch is an unincorporated community in Cascade County, Montana, United States.-Geography:Monarch is located in the Little Belt Mountains of central Montana, southeast of Great Falls on US Highway 89 in the Lewis and Clark National Forest...

,through the Sluice Box Park, and flows through Armington

Armington, Montana

Armington, Montana is a village in Cascade County, Montana near the town of Belt, Montana.-History:Armington has a history of being a commercial hub for Farmers, Ranchers, Miners and others living in the surrounding areas...

 and Belt

Belt, Montana

Belt is a town in Cascade County, Montana, United States. The population was 635 at the 2000 census. It is part of the Great Falls Metropolitan Area.The town's main street is called Castner after its founder, John Castner...

. It finally joins the Missouri approximately 15 mi (25 km) northwest of Great Falls of the Missouri

Great Falls, Montana

Great Falls is a city in and the county seat of Cascade County, Montana, United States. The population was 58,505 at the 2010 census. It is the principal city of the Great Falls, Montana Metropolitan Statistical Area, which encompasses all of Cascade County...

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