What do you do when you go to an event that has metal detectors

I went to a car show today with my dad, we bought tickets turned around the corner and there was a standing metal detector and "security" (3 elderly ladies and 1 elderly man)was checking people in. I ran back to my car and put my Glock in my lockbox. Then went in. I was just wondering what you guys do in situations like this? FYI they didn't have it posted on the door that handguns were prohibited. via /r/CCW https://ift.tt/2uUd8Q3