So, I just recently wrote up my My Travel Memories for Lexington (and maybe Louisville) Kentucky. My photo album has us going through Springfield in 1980 and then has some things from Lexington. In the process of scanning in postcards, I found one that my mom mailed to me, postmarked 1983, that references our first trip to Cincinnati.
But all of the photos of Cincinnati that I can find are from 1987. Our 1980 photo album abruptly jumps to my first date, in 1982, after Lexington.
So, after discussing possibilities with my dad, we have come to the conclusion that the trip to Cincinnati referenced in that postcard must have been in 1980. If I eventually find some evidence that it was in some other year (despite Cincinnati being out of the way for any of our other destinations) I will change it, but the way things stand now, it sure looks like we were there in 1980, so I will write it that way. I think we also went to Detroit that year, and perhaps Cleveland, as well.