Effigy Mounds National Monument preserves more than 200 prehistoric mounds built by pre-Columbian Mound Builder cultures, mostly in the first millennium CE, during the later part of the Woodland perio
Big Bear Mound at Effigy Mounds National Monument
An entrance to Effigy Mounds National Monument
Lidar-derived image of Marching Bears Mound Group, Effigy Mounds National Monument.
Woodland conical mounds at Effigy Mounds National Monument, Sny Magill Unit, Clayton County, Iowa
Mississippi River
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The Mississippi River is the primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri. From its traditional sourc
Effigy Mounds National Monument
…takes in the western edge of the effigy region. The North Unit (67 mounds) and South Unit (29 mounds) are located where the counties meet along the Mississippi River. They are contiguous and easily accessible. The Sny Magill Unit (112 mounds) is approximately 11 miles (18 km) south of the other units, and offers no…
The source of the Mississippi River at Lake Itasca
The first bridge (and only log bridge) over the Mississippi, about 25 feet south of its source at Lake Itasca
De facto head of navigation, St. Anthony Falls, Minneapolis, Minnesota