If you come at 3 do you have to leave at 4 or can u finish walking around

You have to walk towards the exit but you aren't forced out immediately.

I'll say yes in a way. Cos at 4 they start cleaning up. But you won't be forced out.

Generally about a half hour after the zoo closes they begin to do a sweep of the grounds to make sure everyone is leaving and out by 1 hour after the gates close.

You can stay but kost of the things will be closed so not much of an advantage to stay anyway, but no one forces you out