In the early 1960s, Iowa 21 was straightened through Keokuk County near Guernsey and Deep River. This caused the eastern end of Iowa 85 to move east back to the point where it had turned into an east–west route in the 1930s.
During the early 1960s, the course of Iowa 21 was altered through Keokuk County near Guernsey and Deep River. As a result, the eastern endpoint of Iowa 85 shifted back to its original orientation as an east–west route in the 1930s.