It's free so stay as little or as long as you like. Last time I took my 11 y.o. he was so into it we spent 2 hrs. And this is after probably 5 or 6 visits!
We were there 2 hours before they closed, but we want to go back soon. There is so much to see! Fascinating!
People have hit the highlights in half an hour. And other people have spent an average of 45 to 60 minutes.
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