The Folkert Mound Group of Hardin County, Iowa is a collection of 27 prehistoric mounds on the bluffs above the Iowa River, in a variety of shapes, including linear, compound, conical, and an enigmatic cruciform mound. The earliest map of the mounds was made by John Hotopp in 1974,[2] and the mound group was mapped in detail in 2006.[3]
The alignment of the cruciform mound is especially interesting to researchers.[4] Horton[5] felt the cruciform mound aligned with the 11th century Crab Nebulasupernova. However Lensink[6] felt there was little evidence of this possible alignment. An apparent alignment of the largest conical mound, A, in the south with the end peaks of the cruciform mound, X, and an alignment between Mound X and the end of longest mound, T, has been postulated, but the meaning of these alignments is unknown.[7]
^Hotopp map of 13HA30, 1974, on file, Office of the State Archaeologist, Iowa City.
^Collins and Whittaker (2007) Digital Mapping and Ground-Penetrating Radar Survey of the Folkert Mound Group (13HA30), Hardin County, Iowa. Contract Completion Report 1395. Office of the State Archaeologist, University of Iowa, Iowa City.
^Horton (2007) A Star Explodes! A.D. 1054: Did Prehistoric Native Iowans Witness and Record this Titanic Stellar Event? Newsletter of the Iowa Archaeological Society 57(3):1-2.
