Youtube video on the change from private rail service to Amtrak.
Privately run intercity passenger service in Milwaukee was a thing of the past by early 1971. The Federal government had formed Amtrak to remove the burden of passenger service from the railroads and insure that core passenger routes remained active.
By May 1st, when Amtrak rolled into Milwaukee, things had changed. Milwaukee Road’s Hiawatha and C&NW’s bi-level Streamliners were out, but Amtrak’s Empire Builder was in. Direct rail service was now available all the way to Seattle, but one could no longer travel to Green Bay!