Today’s Lake Calhoun Center, located at 3033 Excelsior Boulevard, was once the American Hardware Mutual Insurance Company. It’s current sleek/suburban glass facade was added in 1989 when the building’s fifth floor was greatly expanded.
This 1957 Architectural Record ad was all about stainless steel and featured the building.
Also worth noting is that Excelsior Boulevard appears less wide in this +/- 1957 aerial. Today, those concrete steps leading from the building (across the drive lane) sit just a couple feet off the sidewalk, which is adjacent the street. In addition, note how the fifth floor was not a full floor. In fact, back then it was primarily the board room.