Go at your own pace but plan 1.5 hours depending on your interests.
No. It's best to go when it's not busy.
It's a go at your own pace kind of deal. If you're cruising through it, it'll take an hour - maybe less. If you want to read the plaques and really take it all in, you could spend the whole day there. I would say 2 - 3hours is a common amount of time to get through it.
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