All the temporary wooden tunnel structures for people to walk through in the under construction areas of the train and bus station smell horribly of pee, and because they're somewhat enclosed (which I guess is why people pee in them), the smell never goes away.

I hate the smell of old rancid pee and it is literally EVERYWHERE in any area that is even slightly enclosed or obscured from the street or sidewalk. And in public elevators and stairwells.