Iowa 394 was added to the primary highway system on July 1, 1980.[4] In 1991, Iowa 394 was identified as part of the Avenue of the Saints corridor, which was envisioned as a high-speed highway connecting St. Louis, Missouri, and St. Paul, Minnesota. Through the late 1990s and early 2000s, construction occurred on the new four-lane Avenue of the Saints highway. In August 2001, the Iowa Department of Transportation gave the corridor a single route number — Iowa 27 — in order to aid drivers navigating the route. Shortly thereafter, signs for Iowa 394 were removed from Iowa 27 south of US 218.[5] While signs were removed in 2001, Iowa 394 still existed on paper until March 15, 2005. At the same time, the portions of the highway that were not bypassed by the new four-lane highway were re-designated as Iowa 460.[4]