Geologically young when compared with ancient rivers such as the Nile or the Amazon, the Minnesota River is only about 12,000 years old. It occupies a channel that was cut by the Glacial River Warren, when it drained Glacial Lake Agassiz, the largest lake to have ever existed. This all occurred at the end of the last glacial age, when the glaciers covering Minnesota, in some cases to a depth of over a mile, melted away. seal of Minnesota Department of Transportation
Starting at the South Dakota border, at Browns Valley, the Minnesota River is the state's second largest river. It joins the Mississippi at the foot of Historic Fort Snelling, after traveling a distance of some 355 miles. By geological definition the Minnesota is an "underfit river," the term applied when a river occupies the channel of an earlier river. While the ancient valley is up to two hundred and fifty feet deep and in places 5 miles wide, the Minnesota is just a shallow, meandering river. During flood stages it swells beyond its banks, due to runoff from its extensive drainage basin.
History is abundant along its banks. Exposed by the waters are rocks that are more than 3.8 billion years old, attesting to the age of the earth. Ruins stand today as reminders of former homes, villages, military posts and sanitoriums that once served the residents of the area. Indian villages and crossing sites that predate the European settlement of the region, are also found along its course. Hundreds of steamboats once slowly traveled the river. Their use ceased with the coming of the railroads.
While the water flows by in an endless trip to the sea, and the life style changes with each passing year, the past will always be present here in the Minnesota Valley.
seal of The Minnesota Historical Society, Instituted 1849
Erected by the Minnesota Historical Society