Detroits zoo is not too bad. The zoo is kind of boring but does have a few stand out, excellent exhibits. The coolest exhibit by far is the polar bear exhibit, don't bother going if this one isn't open. They have a tunnel that goes underwater and you can see the polar bears swimming. It's pretty cool.
Whatever you do, don't pay to go on the moving ride/simulator thing. I have had more exciting times watching my bigscreen at home.
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