EASY!!! it is the Missouri RIVER.
The Missouri River.
The Missouri River starts in Montana, flows through North Dakota and South Dakota, then along the border between Nebraska and Iowa, then flows across Missouri and into the Mississippi river near St. Louis, Missouri.
the longest river in the United States; arises in Montana and flows southeastward to become a tributary of the Mississippi at Saint Louis. <><><> But NOT to the Gulf of California.
The Little Bighorn is a 138-mile-long river that begins in northern Wyoming and flows northward into Montana.
There are so many bodies of water in the US. The Montana river flows from Montana to the Mississippi River.
The Missouri River starts in the Rocky Mountains of western Montana. It flows through Montana, North Dakota, South Dakota, Nebraska, Iowa, Kansas and Missouri where it flows into the Mississippi River.
The major river that flows into the Mississippi River just north of St. Louis, Missouri, is the Missouri River. The confluence of the Missouri and Mississippi rivers occurs near the city of Alton, Illinois.
The Missouri flows more or less in a North-west to South-East direction before it joins with the Mississippi just north of St Louis.
The Missouri River starts in the Rocky Mountains of western Montana. It flows through Montana, North Dakota, South Dakota, Nebraska, Iowa, Kansas and Missouri where it flows into the Mississippi River.
The Missouri River flows through the state of Montana in the Rocky Mountain region.
The Missouri River empties into the Mississippi River at St. Louis.