Its western terminus is at U.S. Route 65 northeast of Iowa Falls.

It turns eastward there and runs through Aplington before meeting Iowa 14 in Parkersburg.

At the time of designation, the highway went from Grundy Center northward to Cedar Falls.

In August 1932, the segment from Grundy Center to Parkersburg was renumbered as Iowa 14.

In 1986, when U.S. Highway 20 was expanded to four lanes to the Black Hawk/Grundy County line, Iowa 57 assumed 20's old route from Cedar Falls to Parkersburg.