Just to the southwest of the Creighton University campus is the North Freeway interchange, where US 75 leaves eastbound I-480 and joins westbound. The North Freeway was originally planned to be an Interstate Highway, "I-580", connecting northern Omaha to downtown, but this project was canceled with the interchange in midst of construction. A number of so-called ghost ramps can be found, but these are being eliminated during the reconstruction of this interchange. Here, I-480 turns to the east towards Council Bluffs, Iowa. I-480 passes between the NoDo and Downtown Omaha neighborhoods. Farther east, it dips to the southeast near CenturyLink Center Omaha, part of the "NoDo" neighborhood. Immediately before crossing the Missouri River, U.S. Route 6 joins I-480 to cross into Iowa. This bridge over the Missouri River was constructed in 1965 – 66 to replace the old Ak-Sar-Ben Bridge which had been the first highway bridge across the river in this area.