Personally seen? If that's the case, well, I've only ever been to three zoos in my life, namely Toronto Zoo (one of the greatest zoos in the world, just sayin'), Buffalo Zoo and the former Zooz, which was reworked into the much better Safari Niagara. Zooz was a miserable experience all around, honestly. I mean, it was nice to spend time walking around on a lovely day with my beloved grandparents, but the animals all seemed inactive and a bit sad in their shabby enclosures. Buffalo Zoo used to kinda suck too, I went there as a kid on a school trip and just from a design standpoint, many of the enclosures were these archaic concrete pits. Judging by the photos I've seen in recent years though, they greatly improved too.