River near the Luther College campus. It heads north past the unincorporated community of Burr Oak. north of Burr Oak, US 52 crosses the state line into Minnesota. History US 52 was designated in Iowa in 1935, replacing US 55 from Iowa 117 near Sabula to the Minnesota state line north of Burr Oak. US 52 crossed the Mississippi River at the recently constructed Savanna–Sabula Bridge, which opened in 1932. The section of old US 55 from Iowa 117 to Dubuque ran concurrently with US 67 until 1967 when US 67 was truncated back to the intersection with US 52 on Iowa 64. From 1963 to 1967, rather than following its alignment from Dubuque direct to Luxemburg, US 52 was realigned to instead follow US 20 to Dyersville and then Iowa 136 to Luxemburg while the original alignment was being rebuilt. During this time, Iowa 136, which previously ended at US 52 in Luxemburg, was truncated back to US 20 at Dyersville, but it was redesignated along this segment after US 52 returned to its old alignment. In the mid-1990s, US 52/US 61/US 151 in Dubuque was shifted onto a new expressway through downtown Dubuque, which means the three U.S. Highways no longer intersected US 20 directly. Iowa 946 was designated as a connector route to provide direct access to US 20 from the three U.S. Highways. The alignment of US 52 from Dubuque direct to Luxemburg was a particularly curvy and dangerous section of the route. A study conducted by the Center for Transportation Research and Education at Iowa State University, found that between 2002 and 2006, over 240 accidents with six fatalities occurred on this alignment; the study supported this section's discontinuation as a U.S. Highway. In April 2013, the City of Dubuque and surrounding jurisdictions proposed rerouting US 52 so that it would match the existing route from Clinton, Sabula and Bellevue, but now head south concurrent with US 61/US 151, bypassing Dubuque, rather than heading north, into Dubuque. Once reaching the proposed Southwest Arterial, US 52 would turn onto that new highway and at its end, share an alignment with US 20. US 52 and US 20 would continue on to Dyersville, then US 52 would split off and continue to Luxemburg. This new routing would be similar to US 52's alignment from 1963 to 1967. This new alignment of US 52 officially took place on