Editing Musselshell River (section)

{{Use American English|date=February 2025}}
{{Infobox river
| name              = Musselshell River
| image             = 
| image_size        = 
| image_alt         =
| image_caption     = 
| map               = Mt-rivers.gif
| map_size          = 300px
| map_alt           =
| map_caption       = Map of Montana rivers with the Musselshell in the center
| source1_location  = 
| source1_coordinates= {{coord|46|18|56.1|N|110|39|53.7|W|name=South Fork Musselshell River}}
| source1_coord_ref = {{r|gnis}}
| mouth_location    = 
| mouth_coordinates = {{coord|47|22|29|N|107|56|35|W|name=Musselshell River|display=inline,title}}
| mouth_coord_ref   = {{r|gnis}}
| subdivision_type1 = Counties
| subdivision_name1 = [[Petroleum County, Montana|Petroleum]], [[Phillips County, Montana|Phillips]], [[Rosebud County, Montana|Rosebud]], [[Musselshell County, Montana|Musselshell]], [[Golden Valley County, Montana|Golden Valley]] and [[Wheatland County, Montana]]
| progression       = 
| length            = {{convert|342|mi|km|abbr=on}}
| source1_elevation = 
| mouth_elevation   = {{convert|2247|ft|m|abbr=on}}{{r|gnis}}
| discharge1_avg    = {{convert|253|cuft/s|m3/s|abbr=on}}<ref>Near Mosby,~60 mi from mouth</ref>
| basin_size        = {{convert|9570|mi2|km2|abbr=on}}
| river_system      = [[Missouri River]]
| tributaries_left  =
| tributaries_right =
}}

The '''Musselshell River''' is a [[tributary]] of the [[Missouri River]], {{convert|341.9|mi|km}} long from its origins at the confluence of its North and South Forks near [[Martinsdale, Montana]] to its mouth on the [[Missouri River]].  It is located east of the [[Continental divide]] entirely within [[Montana]] in the [[United States]].{{r|mtfish1}} Counting its pre-confluence tributaries, it measures {{convert|425|-|500|mi|km}} in length.{{r|mtfish2}}{{r|mra}}

It rises in several forks in the [[Crazy Mountains|Crazy]], [[Little Belt Mountains|Little Belt]], and [[Castle Mountains (Montana)|Castle mountains]] in central Montana. The main branch is formed by the [[Confluence (geography)|confluence]] of the [[North Fork Musselshell River|North Fork]] and [[South Fork Musselshell River|South Fork]] in [[Meagher County, Montana|Meagher County]], about {{convert|25|mi|km}} east of [[White Sulphur Springs, Montana]], just east of [[Martinsdale, Montana|Martinsdale]], north of Martinsdale Reservoir, and just west of Meagher County's border with [[Wheatland County, Montana|Wheatland County]].{{r|mra}}{{r|hwy}} The North Fork flows south from the Little Belt Mountains through Bair Reservoir, then southeast. The South Fork flows northeast from the Crazy Mountains. From the confluence of these two waterways,  the main branch flows roughly due east past [[Two Dot, Montana|Two Dot]], [[Harlowton, Montana|Harlowton]], and [[Roundup, Montana|Roundup]], then turns north just past [[Melstone, Montana|Melstone]], and continues to the [[UL Bend National Wildlife Refuge|UL Bend]] on the Missouri River at the beginning of [[Fort Peck Dam|Fort Peck Reservoir]].{{r|mtfish1}}{{r|mra}}{{r|hwy}}

The Musselshell River has also been known as: Cockkleshell River, Mahtush-ahzhah, Muscleshell River, Mustleshell River, Shell River.{{r|gnis}} The Musselshell was entered by the [[Lewis and Clark Expedition]] on May 20, 1805 and named by them for the [[Freshwater bivalve|freshwater mussels]] lining the bank,{{r|lewcla}} noting in their journals that the [[Hidatsa|Minnetare]] people had given the waterway a similar name.{{r|lewcla1805}}{{r|lewcla1805-1}} The [[Blackfoot Confederacy|Blackfeet]], who hunted buffalo and prepared the meat for winter in the Musselshell area, called it the Dried Meat River.{{r|wpa}}