Would you bet your life that a wolf couldn't escape this enclosure?

That\'s exactly the game you will play if you visit Nanjing Zoo.
(I\'m aware that wolf based fatalities are actually incredibly rare)

Wolves are not good climbers and those trees appear to have near vertical trunks, so yes in this case I would bet my life.

I am surprised and educated! I figured with a run up they could power their way up! Good news for the inhabitants of Nanjing