This is a fun read. https://www.cnn.com/travel/article/backpacking-italy-mess/index.html
I research things to death but I'm still caught by surprise and manage to embarrass myself. Here's a comment I made this morning on a popular post that Nigel has going right now;
my first trip to Europe was in 2014 and while in Rome I went to the Team Store of the local soccer team A.S. Roma. As a sports fan I wanted to get a souvenir, so I was looking at shirts with the team's logo. Back home I wear a large so I picked one out, but the friendly clerk told me that it was never going to fit. I told her I'm definitely a large, and she looked at me like I had two heads and I looked back at her like she had 2 heads. I had no idea that clothing sizes were different from home, but apparently my wife did and was enjoying watching me make a fool of myself as I tried putting the shirt on. Turns out in Italy my shirt size is XXXL.
Anyone else have some good clueless travel stories about yourself that you learned from?