The vast majority of my travel is within the United States, so Frankfurt remains the sole international airport in my flight log to date. I’ve certainly been to others—I grew up in a military family and have lived in both Germany and the United Kingdom, but both were when I was much younger, and I don’t particularly remember the airports.
I think the biggest thing that surprised me was that, while it was a big airport, it wasn’t as big as I expected. It’s hard to remember, when I routinely fly through ORD and DFW, how big those airports truly are; they’ve become my normal “major hub” baseline, and I’m comparing everything to them.