Mental. Honestly mental.
Is it one of those things where if you get a momentum up, like Vinnie Jones in X-men 3, you can keep going ok? Because it's hard enough walking on some of it.
They were running on ice too. That's right... ICE. Not the leftover snowy bits with purchase on them, or gritted roads.
I also saw a girl struggling to work wearing 2 inch high heels. They haven't even invented a word for what I think of her yet.