In southwestern Ohio west of Elizabethtown, the Rennert Mound Archeological District covers about 40 acres and preserves one surviving Native American mound, with the remnants or likely locations of two others that once formed a small complex. The main mound, also called the Minnie Rennert Mound, was dug into by locals but still keeps its original shape and has never been professionally excavated, leaving its builders uncertain, though it may be Adenan or Hopewellian. Nearby chert lithic cores and the possible bases of the lost mounds add to the site’s importance. John Rennert helped protect the surviving mound, and the district was listed on the National Register of Historic Places in 1975.