The Mound is of glacial origin, though it was for a long time thought to be an Indian burial ground. It is a kame -- a hill or ridge formed by glacier deposits at the mouths of ice tunnels or channels. The Mound was formed during the recession of the Wisconsin ice sheet ,the last glacier to invade Iowa, many thousands of years ago. The Mound rises 170 feet above the surrounding flood plain and reaches 1,655 feet above sea level. The mound runs northeast to southwest about one-third of a mile; portions of its summit are only a few yards wide. The mound is open to the public year round and is accessible by a concrete and blacktop road two miles south of Iowa 9.