Sea World Orlando dolphins 2004.
What Gabriel was looking at in this picture...flickr.com/photos/jasmic/18604923/in/set-438878/
I know that these magnificent creatures are not in their natural environment, but if they are to be kept in a captive environment then something like this has to be the standard. The area they lived in is really large, and they did look like they were really having fun. I am no expert in these matters, but I felt that they were well looked after and content.