I can't remember where it was now, somewhere like Portsmouth, where some morons had fitted a speed bump just after the height barrier, so if, like me, you fly close to the wind, you get a lovely surprise as your front wheels climb the speed bump.
I used to get my children to watch through the moon roof, and if I hadn't, I would have had a nice repair!, that was one of the 2 times I've reversed back out of an entrance because of idiotic car park design.
The other was a new fire suppression system in Cambridge, where some pipework was lower than the height restriction bar.