We spent 2.5 hours there doing the self guided tour and didn't get to see everything because we came too close to closing time. It's a beautiful, magnificent place to tour, I'd air on the side of giving yourself too much time rather than not enough.
We spent 2 hours there on a rainy day don't the self guided tour. We didn't do much outside due to the rain. So we took our time inside. We would have been there longer if it was nice out.i hope this info helps.
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