Iowa 122 begins at a diamond interchange with Interstate 35 on the eastern edge of Clear Lake.

[3] At Jefferson Avenue, Iowa 122 separates into a pair of one-way streets, remaining in this configuration through the downtown area where the Park Inn Hotel, one of Frank Lloyd Wright's few commercial buildings, resides.

The one-way streets rejoin at Massachusetts Avenue forming an undivided four-lane road.

In that year, the state completed work on a new freeway segment of US 18, bypassing Mason City to the south.

In 2003, the segment between Mason City and Nora Springs was turned over to Cerro Gordo County.