It's the city where the Cunninghams live out the sunny 1950s on "Happy Days"
Happy Days (
TV 1974-84) The Cunningham family live through the 1950s with ... of life in the 
mid-1950s to mid-1960s USA, set in the Midwestern city of Milwaukee, Wisconsin 
.... was a flop but luckily the gang returned to Happy Days for the rest of it's run.