Chleo... Here is a suggestion about the wording of your question: It should be "Have you ever visited a zoo." Because you're asking the question to people from all over the world, then you need to be less specific and ask if they have visited 'any zoo, anywhere in the world' = a zoo. If we both lived in the same city, and there was only one zoo in our city, you would ask me if I have ever visited THE zoo (the specific zoo in our city). Yes, I have visited several zoos when I was very young. I enjoyed seeing all the wonderful animals, but now that I'm older, I feel sorry for the animals because they should be living free in nature and not in cages.

Oh yes! Where did you visit it?