While looking through old aerial photos of Sioux City I noticed two very little changes to its alignment that I hadn’t included in my map series. (In fact, if I didn’t make this post I doubt they’d be seen at all.)
First, US 75 and the railroad tracks on the south side were in a ramrod-straight diagonal until they were bent around the new I-29/I-129 interchange.
Second, there used to be a slightly different route through Floyd Park south of Transit Avenue, which wasn’t changed until 1981 or 1982. Much of the old road was taken out for the Floyd Park golf course, but there is a short stretch of Williams Avenue and this odd stub of a driveway (Google Satellite View).
I’ve made those changes, and also waffled slightly on how much of US 75 in the city could qualify as a thicker expressway-type line. I may drop that entirely later.