The Mississippi River begins at its source at Lake Itasca in north central Minnesota. It is North America's third longest river, ranking fourth globally when it joins the Missouri River to form the Mississippi-Missouri River system.
The Mississippi River meanders for 2,350 miles from central United States towards the Gulf of Mexico where it empties. Its length varies according to different surveys, which is attributed to the annual changes in deposition, occurrence of erosion in the area, formation of new courses or blockages of the river's flow.
The National Park Service of the U.S. Department of the Interior and the Mississippi National River and Recreation Area both agree at 2,350 miles, while the Itasca State Park has the river's length at 2,552 miles. The Mississippi River spans 20 to 30 feet at Lake Itasca.