The famous cookie-cutter moats at the Miami Metrozoo. So much of the zoo has the same exhibit design, but it enables the animals to have spacious, somewhat naturalistic exhibits.
This photo shows a white tiger in the distance, and from the water to the surface of the exhibit I would hazard a guess and say that it was 14 feet deep. It is probably twice that or more in width to prevent the big cats from making lunch out of the gawking tourists.
