Recently I visited Chester Zoo along with friends from the Wildlife Art Society International.
This is an enormous site, and they've certainly done wonders in creating some terrific environments for their animals - as zoos go, I really think they have pulled out all the stops in making each area as sympathetic as possible for the animals there, as well as very educational for visitors.
I was very pleased to see a young Orang-Utan behaving very naturally, and also the beautiful Sumatran Tigers - I can visualise making something of this tiger slightly "camouflaged" behind grasses or other undergrowth..