Turkey River Mounds State Preserve
Turkey River Mounds State Preserve is a historic site located near the unincorporated community of Millville, Iowa, United States. The preserve contains thirty-eight of forty-three Native American mounds located on a narrow Paleozoic Plateau at the confluence of the Mississippi and Turkey rivers. They vary in size and shape and are to in height. The conical mounds range from to over in diameter. The linear mounds vary from to in length. There is one effigy mound in the shape of a panther that is long and wide. There are also compound mounds in the preserve. The mounds were constructed during the Woodland period. They were used for burials and ceremonial places, and are now protected by law. The preserve is also home to a variety of trees, prairie grasses and flowers.
The mounds were first surveyed in 1885, and Ellison Orr studied them in the 1930s. People from Dubuque, Iowa bought the property in 1934 and gave it to the Iowa Conservation Commission in 1940. Other archaeological surveys were undertaken in 1964 and 1973. It was dedicated as a state preserve in 1968 for its archaeological, geological, and biological qualities. The preserve was listed on the National Register of Historic Places as a historic district in 1990.