At Altoona, the route again overlaps I-80 until Newton, where it splits away from I-80. The highway passes near or through the cities of Kellogg, Grinnell, Victor, Marengo, the Amana Colonies, and Tiffin before entering the Coralville / Iowa City area. Through Coralville and Iowa City, US 6 has no direct access to I-80, I-380, or US 218; other routes like Iowa Highway 1 (Iowa 1) and Iowa 965 provide direct access. From Iowa City, the highway heads to the east-southeast through West Liberty and Atalissa. Near Wilton, the route heads north to I-80 where it again overlaps to Davenport. At Davenport, US 6 then follows I-280 and US 61 before entering the city. On the eastern side of Davenport, it joins I-74 and enters Bettendorf before leaving Iowa for Illinois.